OMG this is so annoying. Its not as evident in PvE because I get lazy and play in slowmotion even using the mouse. But in PvP the behavior is extremely frustrating. My guild mates always asks me why I get so pissed during PvP. I die with a smile and I loose with a smile but this stuttering problem is starting to make me go mad...
Forgot to mention that I had a similar problem in APB:Reloaded.
I ended up buying a new keyboard (mechanical) and use PS2 instead of USB. This is not the problem in SWTOR.