Tailcap measurements from my totally uncalibrated DMM using Turnigy LSD 2400 mAh batteries were,
Single battery, low .02 A, med .25 A and high 1.58 A.
Two batteries, low .01 A, med .13 AmAh and high .65 A.
The light is slightly brighter on high with a single battery on my light measuring device.
My review on the driver can be found here.
Edit. I should mention that the difference in readings would be attributed to the power supply used during testing and a different DMM used for the measurements.
The LED’s are wired up so they are all in parallel. If the driver is putting out its advertised .5 amp each led would be receiving 1/4 of .5 amp being .125 A. Not a lot hence I’m not sure if this light would be Dale approved. 
Of your not the only one with a small head as others here will tell you with the many PM’s I’ve had to other members trying to understand things. :disappointed:
This light was specifically built around this optic. The X^ Monster light Dale sent me was made by him before he had a lathe. He used his exceptional skills to make an adapter to fit the optic into the X6.
The mini C8 can be adapted with a pill to accept the 22mm optic. This uses a AAA battery.
As far as of the shelf hosts go I haven’t bought anything for specific uses like optics etc.