What an amazing thread! I think I can list a lot of things but as an overview, and from other conversations I've had, I'd say anything massively inconsistent would be difficult for anyone in therapy.. messing around with timings of sessions or locations of sessions would be a biggie for me.

I think its useful for T's to know what to avoid.. but still as someone said, anyone well-trained wouldn't need to look it up.. they'd know appropriate behaviour instinctively.. I hope..