I think it is a nice Idea; we could implement it as an easy mode assist feature. I think it could go well if:
- You lost the tile-breaking points you gained in the last move, even have a score penalty.
- You have a limited number of times to perform undo per session.
- The MeanTank would not go back.
- The last Move performed still counts as a spent.
- Any/all of the above.
Certainly, we could look into it.