Currently the game analysis allows you to look through your games and see the mistakes and blunders you made. A handy training device would be to have the tactics trainer use those mistakes as the position for your tactics puzzle.

Practice on situations where you have made a mistake in the past and maybe lessen your errors in your games.

I've done that manually for myself over the years: analyzed my games with a good engine, then built tactical flash cards from the best tactical oversights by my and my opponent. I presume an application for doing that automatically could be built. Not sure if one exists in any of the mainline programs. If anyone knows, chime in.

Interesting. 

The easiest way to program this would probably be to:

-'tag' problems in the Tactics Trainer based on theme.  Examples of themes could be, "Night forks" or "f2/f7 sacrifice."  These tags wouldn't be displayed, of course or we'd know what to look for.

-have the analysis engine similarly 'tag' missed tactics.

-have the Tactics Trainer give you problems in a ratio proportionate to the tactics you missed in analysed games. 

Neat idea.

Actually I'd be impressed enough if the analysis engine could keep track of the types of tactics i tend to miss so I can work on them.