I'll also mention this, take it with a grain of salt...
I have never wiped my apps and data, except for experimenting with ROMs to see if they really worked better with this kind of complete wipe or not... This is going way back to my early DroidMod days... In my experience the complete wipes don't help, and I've successfully run CM, BB, SS, old DroidMod, and a number of stock-rooted builds...
The reason the ROM developers encourage complete wipes is that that is the only way they can test and have consistent results, especially with all the theming they frequently do. But you can bet that Verizon, Moto and Google *do not* require complete wipes, they'd never get over the complaints and help requests in their service departments.
The only time I do a complete wipe is just before I am going to restore a backup.
I always wipe cache before loading a build of any kind. Cache gets corrupted very easily and should be wiped occasionally anyway, especially if you're experiencing any kind of random reboot...
I would always encourage people to try loading their chosen builds not to do a complete wipe first. It will complicate your booting process tremendously if you do the wipe. especially if you have a lot of applications (I've got over 100), and you'll loose your phone log and all of your email and messaging history... Even backup programs have trouble restoring these things without getting Google synchronization messed up.
BTW, keep in mind that P3's stock-rooted-odexed FRG22 is the complete file, a big one like the larger FRG01B file in another thread here... It has all the files that the larger FRG01B has in it (and more) except it doesn't have the upgrade scripts.
Just my .02... Enjoy dancedroid