Firstly, I don't understand anything. Why on earth would west be thinking about covering if he had the ♠Q? But on the larger point, in my opinion, it would be best if the laws retained the right of the players to think as much as they needed to, and the standard for "could have know that the variation in tempo would mislead declarer" was quite a bit higher. Even if it leads to a little bit of coffeehousing, it's not clear to me that would be as devastating to the game as some people suggest. If you have such great table feel that you can reliably make reads from your opponents' tempo, I bet you have good enough table feel to still get a read even when they're allowed to vary it randomly. And even if does mean that experienced players have to give away some of their edge playing against less experienced opponents, is that such an awful thing?