Alright so I tried the Fsmash to see how far it can hit without directly hitting the opponent. This range is actually pretty far, as the opponent can be an extra body length away from the hammer and it still hits.
This does 5% damage and still has pretty good knockback.
Also, I was originally wrong about how much the JEt hammer does in the air. It actually does 28% max.
Also I spammed Dedede's moves to see how much less damage it did with the New diminishing moves in Brawl. I only tried it on Waddle Dees and his Fsmash and these were the results in terms of how much damamge for each hit.
Wd - 5,4,4,3,2,2,2,2
FSmash - 24,21,20,19,16,14,13,11,
Also to T-major. The Jet hammer cant hit behidn you.