I've run DNP likely more times than most people here.
7-8 times, at dosages from 200mg -> 800mg
Here is my anecdotal experience:
High-dose DNP is counterproductive.
Anything much over 200-250mg and the carb cravings often cause you to binge at the end of the day, undoing any progress.
And the increasing lethargy + general malaise from escalating dosages mean that your drive to exercise and NEAT activity tend to decrease, again offsetting any increase in BMR.
Every time, I wound up losing more weight by doing 200-250mg for a longer period, than trying to short-cut and do 400-800mg for a brief 2-3 week burst.
No, not physiologically possible with mitochondrial uncouplers.
I used to have a lengthy DNP guide that was fairly popular on an old, defunct forum called FitMisc. Unfortunately it's gone without any archives =/