Out of order albums in iTunes / on iPod

I have some albums in my iTunes library that would not sort or play in the correct order, and it caused my iPod and iPhone to play out of order too. In particular, Schism would play first on Lateralus and then the rest of the album would play in order (without Schism playing twice.) It turns out that only Schism had an 'Album Artist' tag in addition to the tags the rest of the songs on the album had, like 'Title' and 'Artist'; iTunes sorts albums by 'Album Artist' before it sorts by 'Artist'. I erased the 'Album Artist' tag on Schism and synced my iPod, and everything plays in order.