@glacial Yes and no.
In my case, I was signed in on the same iTunes account on two different Windows accounts. However, because of the way Windows (and Linux) give each user their own folder, I had to do some minor tweaking to get iTunes to store stuff in the “All Users” area so that both of us could access it. .
As for syncing, this is where a little thing called DRM (Digital Rights Management) rears it’s ugly head.
See, iPods are registered, as are iTunes accounts. If the iPod you try to sync is registered to a different iTunes account than the song you are trying to sync, hilarity ensues… and by “hilarity”, I mean disappointment and rage. I don’t have that problem so much since most of my music was ripped from CDs and thus is DRM-free, Songs bought through iTunes, however, have Apple’s DRM all over them, so iTunes may balk when the numbers on the iTunes account and those on the iPod don’t match.
I simplify things by avoiding iTunes altogether.