I have been considering the factory wipe along with the root. Neither are my preferred option, but if I am left with no other choice...
Doing a factory reset is a bit of a hassle, but it wipes everything off the tablet and resets the firmware which may be "glitchy" (a highly technical term).
If you sync your contacts, calendar, etc. through Google, they will resync again automagically, so no issue there. You simply need to install any apps you want again, and transfer over songs, videos, etc. If the reset fixes the time bug, then I think the hassle of the reset is well worth it.
For perspective, every time I do a firmware update on my phone or tablet, I do a factory reset before the update, and after. This gives me a clean setup of the new firmware, and I've never had issues that others have complained about when simply updating and no doing a reset. Either I'm lucky, or the reset does a better job with the firmware setup. I consider it to be like wiping my PC and doing a clean install of Windows whenever a major change is made.
So for my Tab, I've only reset it once to update to v3.2, and my phone I've reset twice to update to v2.3.6. No big deal to me and I'm "glitchy" free.