I've been clearing it after every play.

Yes. Clearing the system cache removes the patch. To clear the cache without removing the patch, hold the Left Bumper, Right Bumper, and the X button simultaneously while booting the game. It's convenient, because you can do it every time you start to play.

While booting up the game? or the system...

And is there any audible confirmation that you have done it successfully? Some sort of "you've got 30 lives" sound bit?

I'm at work, played during lunch--downloaded the patch played for a few, quit, cleared the cache and turned it off. My gf just text me saying she turned it on and it didn't prompt her to download the patch. Do I need to manually redownload it now?

Yes, you're supposed to do it while booting up the game. As soon as I push Play Game or otherwise, I start holding down the buttons and don't let go until the title screen shows.

There's no confirmation that I'm aware of. I've never seen or heard one to be honest whenever I've used it. I got the instructions from a post by a Bethesda person from this thread: http://www.gamesas.com/index.php?/topic/1120449-please-read-before-posting/page__view__findpost__p__16522616

It would be better if there was something that acknowledges the cache being cleared, but all we can do is assume it's working as it's supposed to. :/

That's weird. Might want to clear up what she meant by turning it on, because just turning the Xbox on won't ask you to update Fallout. She'd have had to start Fallout.

She's playing Fallout NV and she said it loaded up without asking for a patch.

Ask her to press the Xbox button on the controller to see if it says she's logged in. If she's logged in then I'm stumped. If not, she may have pressed no when it asked (ask her to sign in). I've just never had it not ask me to patch after clearing system cache. Never know though.

That's it, her profile is not signed on to live.

Thanks