Thanks, both of you - and also, you're right Colo, it brings up a realism dilemma.

Anyway I suppose there are two causes for troops pathing unexpectedly: one is that you didn't realize the terrain would work that way, and the other is that you didn't know somebody was going to block you. It sounds like the RMB ghosting method works vs. the first but not the second - but going in slo-mo gives you a fighting chance against the second. I appreciate the tip, including the backspace to stop, motor - I've been doing fast-mo so long I stopped thinking of it as a possibility!