How difficult would it be to allow us to play back through puzzles we have already played?  I would like to learn the positions and the best way is via repetition.  While I have no desire to do 'seven circles' itself, it is basically what I am asking about.

If I could pick (and save?!?!) selected puzzles and replay them at will as a collection - THAT would definately be worth paying for a membership upgrade.  Just imagine having 1000 hand picked tactics puzzles to work through until they were burned into your frontal lobe.

The ability to continuously replay positions is the one advantage that a tactics CD has over Sites like tactics trainer, emerald chess, chesstempo, etc.

Do you think its doable? 

good idea.

as wd be a "rewind" button in the video lessons.

maybe a checkbox that says 'save this problem', you could save an ammount determined by your membership level - just thinking out loud

I was just thinking of asking if there was a way to save selected puzzles. Perhaps by saving the puzzle numbers, and looking them up when you want to try them again. I guess there isn't.