[quote name='Jackie Chandler']You can do that for a certain amount of time (how long it is, I'm not actually sure). But once you reach a certain point, you DO have to be signed in with that account to have access to it. It will show up in your hard drive space, and it won't be corrupted or anything- the game just won't recognize it's there. It can lead to some really annoying things, like Rock Band trying to load songs it knows is on your hard drive, but can't access, and completely kicking you out of your setlist. And for downloadable games, they'll show as Trial versions until you sign in as the other profile.
A quick and easy fix is to just sign in with a second controller. That's what I end up doing the majority of the time with an account I bought a long time ago. But it's annoying to have to sign in as that account whenever I want to use that DLC, if my friends came over and wanted to sign in and play something I couldn't have access to it, and spreading it over the course of a bunch of accounts is just plain confusing. It's just not worth the few extra bucks saved to shackle yourself to that account IMO.[/QUOTE]
It's not tied to a certain amount of time, it is actually tied to the console you originally bought it on. The DRM transfer on tool on xbox.com can put it back on your current console for offline and cross profile use. That can only be used once a year though.