They're not likely to boot into recovery. Stock recovery is useless for diagnostics. They'll load up bootloader sometimes, but that's it.
There is no flashable stock recovery as far as I'm aware. It could be created, but I doubt anyone has done it.
It's a 3G issue. Last time I went to the sprint store, the guy said "let me check something" and for some reason (which even I found odd), he booted it up into Bootloader, then Recovery.
(Seriously, don't ask me why. I have no clue why.)
When he saw TWRP, he asked me if my phone was rooted. I played dumb and said "my friend messed with it. I don't know what he did with it.)
Then he gave me the phone back.
Also, from the ClockworkMod Recovery thread, I tried flashing it through Fastboot and it failed. See below:
Wut does dat mean, kuwait?