So, I followed some advice in another thread I found from a while back where the guy suffering similar symptoms ended up changing the thread usage of ffxiv.exe to only use 4 and changed the process priority to High. So I did that, and guess what... no stuttering all night. I did notice some performance drop though b/c of this... which really sucks. But I guess better than the jittery movement.

So, yeah... wth is up with that?