Right now, I'm running 2.0.6 and Smart A.S.S. refuses to work correctly with RCS enabled. Namely if I select a direction such as NODE, PROGRAD, NML+, ect, it very slowly moves towards the desired direction, but eventually it it gets tired of that and starts using more power, it cant correct fast enough, moves past the direction set, then does the same thing as before. Each attempt gets worse and worse as far as steering error goes, eventually it will flip over and you're in a spin. Even if you manually move close to the direction desired, and then turn on S.A.S.S, it does the exact same thing, just takes longer to get the spinning.

Using internal gyros and/or S.A.S. does not produce this error.

See if 2.0.7 fixed your problem, if not, reopen this and post a .craft so we can check it.