Rystil Arden
First Post
The main skills I can think of that present this problem are Concentration and Jump (and the latter is less significant; I think there's only one maneuver that has its damage output or something based on a Jump check, while other maneuvers are just helped out, but not broken, when used with a +Jump item).
There's one that uses a Jump check as the save DC vs a stun effect. This is right-out insane, so most GMs, even those that allow Bo9S, nerf or ban that one.