I made a brief mention of this in somewes's chat a few weeks ago, but I guess I should probably write it out a bit more thoroughly somewhere more easily referenced.

To save the 8-1 framerule you must:

1. Perform a perfect fast acceleration at the beginning of the level
2. Manipulate subpixel stuff so you can FPG without slowing down
3. FPG

I have explained that you can accomplish step 2 by doing a specific Right->Left->Right wiggle while in the air, but that strat is dumb. somewes said it'd be better if you could manipulate the subpixel stuff just by releasing Right for some number of frames, and he was right.

SO

Instead of doing a midair wiggle, you can achieve workable subpixels by releasing Right for 2 frames while running along the ground. However, the subpixels you end up with can vary. Depending on when you do your Right release you'll be setup somewhere in the range of D50-D80. There is a cycling pattern that relates when your Right release is executed to the subpixels you end up with, but if you do the Right release at no particular time, my observations say you'll get

D80 setup 18.75% (12/64) of the time, D70 setup 7.8125% (5/64) of the time, D60 setup 10.9375% (7/64) of the time, D50 setup 62.5% (40/64) of the time.

Stretches of good frames to begin your Right release (giving you D50-D70 setups) are always at least 7 frames long, so you should be able to find a visual cue somewhere in the level that works for you.

Hopefully this makes sense and hopefully someone finds this useful.