I agree. IMHO Undo matches up ok with things like Reversal, Shadow Blade and Entangling Roots:
- It can’t hit heroes, but it can hit units that aren’t patrolling.
- It increases the opponent’s handsize, but it avoids giving scav/tech bonuses and ignores SQL armor.
- It’s great value against expensive units or units with buffs.
What I think harms it is that you can get very similar effects in the same spec with Stewardess and Prynn’s maxband.