It must be done with the power off, and needs to be done firmly, past the stop, to move the stop. Here is the direct quote from Ken/blade strike of DJI:
My thoughts exactly. Also I bet DJI won't be so quick to fix if you break it during this procedure.
Your only options are to try the DIY fix, which did work for me, exchange it for another at the point of purchase, or send it in for warranty repair. The first is the easiest and quickest, preserving options two and three, if it doesn't work. Option three leaves you without your aircraft for three weeks, and you will likely be sent a used refurb instead. I would opt for options one and two. I have used both. Good luck!
I have had very poor luck with all the early production P4P aircraft, whether from B&H or Best Buy (on units 5 and 6 now). If you can get a late, recent production unit, the assembly quality control seems to be better. Best Buy's 45 day exchange policy for Elite Plus members really helps! I'm waiting to see if the latest firmware update fixes the remaining problems, or whether this last one from Best Buy also needs to go back for yet another exchange! Every additional 45 days helps make sure you get a later version unit. Units in the same batch all tend to have the same issues. It's a fantastic aircraft, once you get a good one!
Sounds like the modeling and stretching technique for PD!
The engineer who came up with this technique must have just returned from seeing his urologist! 
