I just started last night myself and noticed this aswell...

I have one computer running two copies of WoW. I made 2 Dwarf Hunters and logged into the game. Opened KeyClone and started running around. I quickly found that the second instance of WoW would get out of sync with the first (as the OP said, the 1st character might turn 120°the other only turns 100°) so then when I run forward again, the second guy is running off in a completely different direction.