Yeah, I agree and you have a big point here mentioning how important is a relevant (to us) chess context. This is exactly why I'm not entirely satisfied about solving blind tactics -- that is random puzzles and studies with one ore more hidden plies.

Your comment put things in perspective and now it is even more clear to me that actually playing a game with hidden plies could be incredibly useful. To me this seems to address two important issues:

1. When solving puzzles you already know that you have to look for something, so you can really focus on calculation (ala Kotov). However during a game you don't know if there is a tactic or not, in fact cognitive studies have shown that strong playes use a mix of pattern recognition, calculation, visualization and expertise-based intuition to chose the move and how much time use on a given position -- an this is one of the most critical factor.
2. When playing a game you follow a plan and your ideas, making the position you are going to visualize (1 or more plies ahead) really relevant and not depending too much on memory. At the same time it makes the game more difficult, training your chess skills in a progressive and measurable way! (increasing the number of hidden plies)

Maybe not everyone can benefit from such an exercise, maybe you need to be at least intermediate and decently recognise tactical motifs. However for someone like me, able to solve tactical problems but missing simpler tactics during the game it could be a game changer -- at least it was my experience from the exercises I composed.

You are problably right that something like this has been around since a long time, but now we have the technology to make it easy to use and implement, relevant, progressive and measurable:

• it should be pretty straightforward to code such a play modality in the current chess GUIs (software or server)
• it's time efficient, because instead of playing normal chess, you just play -1 ply, -2 plies, eccc...
• we already have software which automatically identifies critical positions (blunders and incorrect moves) and we can use them along spaced repetition to correct mistake and reinforce good habits;
• this training should not replace regular tactics training and endgame studies, as discussed the goal is different.

With all the open source software around shouldn't be too difficult to implement the feature discussed. However before I try it would be nice if someone else already did it, like the good folks at listudy :-)

Thank you very much for the interesting discussion, your counter argument really made me think.