Mod of the type: not much gain but also not much work. I bypassed the two springs of my mini-GT (that already had a dedomed XP-G2 S4 2B). Throw went up from 229 kcd to 241 kcd. So the light became a bit better and a bit uglier.
So the 300 kcd that Vinh gets from the miniGT with a Black Flat can in principle be had with just the springs bypassed, if you go by the luminance table that The_Driver maintains.