[Users] logic of scheduling SelectBoundConds in McLachlan?

Hi. Can someone explain to me why ML_BSSN calls SelectBoundConds within MoL_PostStep? It seems like the kind of once-off routine that would happen near the start of a simulation, rather than something that has to be performed every single timestep.

I wouldn't mind, but while trying to understand why ML_BSSN was evolving so slowly on one of our machines, I looked at the TimerReport files, and saw that SelectBoundConds was taking *much* more time (like 20 times as long) than the actual RHS calculation routines.

Bernard