Milt,
Now that's an interesting thesis ... "... ANY measure of asymmetric thrust will be sideslipping in straight flight whether wings level or banked....".
I have no difficulty with sideslip wings level as the horizontal fin/rudder force accounts for a lateral velocity to generate the slip.
However, if one banks while maintaining straight flight, then is there not a sideslip developed due to the bank - regardless of thrust asymmetry ? Depending on the sense of the slip due to bank, is it not either increasing or decreasing the magnitude of slip due to the asymmetry in thrust ? If this is the case, is there not going to be an angle of bank where the two will balance each other nicely and give nil slip ?
Or have I missed something along the way ?