I purely use mine as a post-game analysis tool.
If I have played a game which I felt could have (or should have) gone a different way,
I will run the game through Fritz and see where the weak moves were
and see if there were any missed tactics... some of which can be very revealing!
For example, I recently missed a smothered mate (in two!) but I wouldn't have known if I didn't run the analysis.
I often use Fritz to help for when I annotate games, also.
It helps me remember certain lines in the opening, some of which have become pet lines,
and it has definitely helped improve my ability to spot tactical shots, both for myself and for my opponent.
I feel as though that if I find something that can be instructive in any way, it is worth annotating
and perhaps even sharing on the forum so that others may learn... or laugh at, as the case may be.
Below is an example... the game containing the missed legacy 🙁
I play Black.