Yes, because Amazon only disables your ability to create new collections. But if you deregister with collections, they remain until you reregister (at which point the collections are refreshed from the server).
The collections hacks (including LibrarianSync) circumvent the UI and modify the database directly, and ixtab doesn't care if you are registered.
Then the firmware sees collections so it assumes you had them before deregistering.
I have not personally confirmed that this works, but it makes sense and IIRC someone else started a similar thread a while back and confirmed it.