I find it funny how the change to ravage/masterstrike and the juggs becoming first target (and therefore dead weight) in arenas happened roughly at the same time <IRONIC>.

Actually, the companion is to blame here. As a sin main I have noticed that years ago, but if you use rocket boost right after cloak (causing the comp to disappear), the cloak will work every time. Edit: Another possibility can be the utility from the last tier that adds aoe slow to the force speed - it will put you in combat again if you use it after cloak (which players often do).