Not sure where you read that, but it is definitely possible (and not even that difficult) to add them. Most of us have just found them to be superfluous in this type of a driver since you are building it from the ground up anyways.
Hmmmm... I think where I got that impression was from the original BLFDD17 thread, but I suppose I could have misread it.
That said, AWESOME! I have a few more details to work out, but I think this is going to work very well for my setups. Thanks RMM..
Built my first one of these drivers using the "800" FET (forgot exact P/N), using the T_K blf-a6 program with minor tweaks. It's in a Convoy C8 host, the original one.
I noticed a significant blink when switching between hi/turbo (full out FET only) and moon mode (PWM value of 4 for the 7135 only). Anyone else notice this strange behavior? I know I've seen this before in some troubling drivers - pretty sure it happened with my stock BLF Mini-01 driver.
That's the SIR800DP.
Regarding the blink---I've seen it before on the BLF10DD/12DD drivers when switching from high to moonlight. That was with the same firmware though, so I'd try and rule that out first, although I haven't heard of anyone else having issues with it.
I fixed my problem with a small pulldown resistor (30K) from the gate to ground. You could try a 22K or 19.1K (you've probably got one on hand) and see how that works. If it doesn't get rid of it, you could double stack resistors to half the resistance then try again.
Thanks Richard! Think maybe it's a side effect from this SIR800DP FET used in this fashion? I'm think'n the "gate" is pin #4 on the FET? Looks like pins #1-3 are all goin to ground, so could just put the resistor over the pins? The Convoy C8 is delivered, but if it bothers the owner, I could look at fixing his. For now, I got a couple more of these A17HYBRID-S boards built up the same way, so I can see if it can be reproduced and experiment with a fix. Is there a downside to higher resistance? Best to go low as possible?
btw, I "only" got bout 5.7A max out of this driver to an old XM-L2 U2 1A on SinkPAD with 22 AWG wires. Definitely expected more, like about 6A. I know it's close, but... I tried another XM-L2 U2 1A LED and got the same max amps. I was thinking the SIR800DP would do as good as an original BLF17DD v1.0 with the original hot vishay FET. I didn't do a head-to-head, apples to apples compare test though, so I'm not sure if my tests mean much at this point.
The SIR800DP is a better FET for our applications than the original Vishay was, so the bottleneck has to be elsewhere.
Yes, you can go across the pins with the resistor. You want to go with as much resistance as possible because the lower the resistance the lower the gate voltage will be which will increase the on-resistance. A very high value resistor shouldn't affect things much.
Oops. yes, higher resistance is better - makes sense - you want to impede the flow from the gate direct to ground as much as possible. So, if 1 works, I should not try another stacked because that would lower the resistance.
So I got my 17mm DD + single 7135 v009 from OSH the other day and noticed something: There is no exposed negative ring on the spring side—it’s all solder mask. The OSH picture (and pics in this thread) shows a ring there. There is only a thin ring exposed on the component side. Looks like I need to do a bunch of scraping or re-order.
Do you guys have a ground ring on the spring side?
My EE X6 triple is getting off to a bad start: The heat sinks are loose (and different widths) and will need to be $himmed, and my driver only has negative on the component side.
Thanks
Hi LED B... You got a similar problem to what I had - accept mine had the spring pad covered, yours has the grnd ring covered. Contact OSHPark support. In my case, they created a new set of 3 boards and sent them to me for no charge. I am still using the bad ones by scraping off the purple layer off the spring pad. I used a rounded edge exacto knife - works pretty good. I dunno why wight left a good portion of the grnd ring covered, may be a good reason..., but I usually scrape off the remainder of the covered grnd ring anyway, and also expand the spring pad by scraping it wider as well. It seems to be the covered portion of the grnd copper layer is slightly higher, so depends on where/how it's mounted if you make good contact or not.
I'm get'n pretty good at scrap'n 
.
Hi Tom:
Trying to picture rounded edge blade. Off to Google I go.
I’ve had problems with too-small spring pads too. It’s either scrape, or scavenge a skinny spring off a 105C driver.
…But I do have a lighted stereo microscope, so these getting-old eyes can see what I’m scraping.
curved edge would be a better description I guess... It's not a straight line edge .. 
Dunno - I got a set of them laying around, and think it's less likely to break a tip off by using the curved edge blade. Google "exacto curved edge" - a pic appears, and that's the one I use.
Oh doh! (Smacking my forehead) Ya, I can see where a curved blade would be better for scraping. Off to Michael’s for #21 or #22 blades.
I usually scrape the ground ring clear and flip the retaining over after drilling the grip holes all the way through. They put a bevel on the inside edge which limits contact with the ground ring, by flipping it over there is a wider area of brass to contact the driver for a better ground. 
I kind of like the obvious gear change when going from Turbo to moon. It’s the system switching to the 7135 chip and turning off the FET.
And I do believe TK does NOT use the 7135 at 255, full on power is the mosfet only.
Next time you go to the dentist ask them for any old tools that they would otherwise throw out. These are designed to scrape plaque off of hard surfaces. I've been using them for years to scrape soldermask or paint, etc.
Good tip on that retaining ring trick - I'm think'n you are referring to an EE X6, or is this in general for lights with retaining rings?
Yes - TK does not use 255 for the 7135 in her stock modes - I change the modes to what I like/prefer. Anyway, the transition is to moon mode, so it's a very low value for the 7135 -- 3 is her default value I believe. The bright blink to me is annoying when you are expecting 1-2 lumens , and is obviously unexpected behavior. Didn't get a chance yet to try RMM's fix - hoping this weekend. Got a Roche F6 (https://www.fasttech.com/p/1658300) delivered today, along with a UltraFire F35 (https://www.fasttech.com/p/1742405) from FastTech. I think I got all the SMD's for the custom Roche F6 driver, and got the boards coming from OSHPark in a couple days - should be an interesting project... TK loves her custom driver based F6. I'll have to see how easy/difficult it will be to get a custom driver in the F35...
You should post a thread on your F6 build. There have been many discussions, but I can’t remember seeing any detailed pics of the insides of one.
Ohh, sorry, didn't take detailed pics of the insides - it's a tight pill cavity, not enough vertical space to piggyback a driver in, and the switch is mounted on the driver. It's a uni-body design, so to work on the LED wires, you have to solder downward quite a ways. I posted bout my F6 fiasco here: https://budgetlightforum.com/t/-/26078, in the hacking thread. I can sort of get the end tailcap to stick now, and modded the "Convoy F6" to get 3A (added 2 R100's), upgraded the wires to 22 AWG, added 22 AWG wires to bypass the springs, upgraded the LED to a XM-L2 T5 5D3 and get bout 800 lumens now with a nice look'n tint, but still with the stock driver.
I see what you mean with little details. Seems like a few folks did the full F6 mod, but not much in details around.
That info about the driver cavity is all I needed to know. Thanks
Not to be denied, I spent 10 or so minutes scraping the solder mask off the spring side negative ring that OSH left on, then cleaned the board and oven reflow soldered all the parts on. This is a very easy board to populate, with lots of room for the Pomona programming clip.
I used TK’s BLF-A6 firmware, with two PWM channels. I tweaked it to match the Battcheck results (for accurate battery testing and LVP) and turned the memory function on.
I haven’t done much testing on a battery, but it’s putting out 5.8 amps at 4.2 volts on my no-sag power supply.
Thanks Wight and everyone else who made this possible.
Cool! Just finished a build using my 2nd one - I ended up scraping off the remaining solder mask on the spring side ground ring, so not as much scraping as you . I put this driver in an e-switch light, the UltraFire F35 from FastTech, piggyback'd in. I drilled a hole straight thru the LED+ pad, then drilled a hole in the stock, stripped driver, used as a contact board (and switch mount), through the center + pad, so my LED+ 22 AWG wire runs direct from the bypass wire of the spring to the LED. Used 3 22 AWG wires in between the stock driver and A17HYBRID-S, and got the better SIR800DP FET. I got an amazing 6.45A measured with a LG HE2 @4.18v, using a XM-L2 T6 4C/Noctigon from Richard. Think I got lucky with a low resistance LED or something... I'm using a PWM value of 4 for moon mode on the 7135 channel, phase corrected not FAST. Occasionally I see a flicker when turning it on in moon mode. Heres' my PWM values for the 5 modes:
#define MODES 0, 0, 0, 0, 80, 255 // Must be low to high, and must start with 0
#define ALT_MODES 0, 4, 24, 255, 255, 0 // for secondary (7135) output. Comment out if no secondary output
#define MODE_PWM 0,PHASE, FAST,PHASE, FAST,PHASE // Define one per mode above. 0 tells the light to go to sleep
With those modes using the T6 4C on a Noctigon with an extra 3/4" copper disc reflowed to the MCPCB, I got the following results:
Mode Amps Lumens
Moon: 0.01A 0.6
Lo: 0.03A 9.5
Med: 0.35A 126
Hi: 1.89A 595
Turbo: 6.45A 1547 @start, 1431 @30 secs
Throw on turbo: 25 kcd (316 meters)
It's a pretty decent spread for 5 modes, but I'd make the Lo a little bit higher - I'd target 12-15 lumens. I can't explain the moon mode amps=>lumens results. Moon doesn't scale to Lo very well, but at these low levels, maybe my light box, or maybe resolution of the amp readings is deceptive.