revert to stock evo

[jfizz88]

i havent really seen anyone answer this directly, so ill ask in the general forum.
is the NAND backup process the way that you would revert your evo to stock rom unrooted? i hear thats how your phone must be to get the 2.2 OTA when it airs

but i think most importantly i just wanted to make sure i can UNROOT lol. i already rooted and if i cant unroot i guess im screwed