Kevin Pacey wrote on Fri, Mar 4, 2016 04:40 AM UTC:
I agree it's an interesting (but kludgy) optional rule worth noting, with 96 2D slices as you've described, Joe.
I'd note that if there's ever a rules enforcing preset for Hyperchess4 on Game Courier (and if or if not it would also use the optional rule as you've described), then it might be feasible & desirable to warn a player whenever his king could legally be held next turn (by the opponent's king) if he does nothing about it, much like a player can be warned if he is in check.