Got my ROM flashed for the first time courtesy of DroidReview on YouTube and more than a few of you on here. But in the vid there was never a mention of wiping the cache and/or partition while in nandroid. I seem to recall that somewhere else on here. Can someone tell me if you're supposed to wipe the cache/partition from nandroid before flashing a new ROM? If so, why (or why not)? many thanks!