It's like Defensive Combat Training, but for your CMB instead. And it only works on a specific maneuver.
So rogues or clerics or whoever can be better at grappling or disarming or what have you.
Is there anything like this out there? Does it seem like something you'd ever take?
There's maneuver mastery, an arcana for magi and a revelation for a couple of oracle mysteries. Some people take it but not often.
Sounds pretty bad, especially for a 3/4 BAB character. The bonus will be small (1-2 at low levels where maneuvers tend to be effective). And non-full-BAB classes usually have better things to do in a fight than be merely adequate at maneuvers. It gets OK at high levels, but much better feats exist.
So rogues or clerics or whoever can be better at grappling or disarming or what have you.
Is there anything like this out there?
Rogue actually has access to several talents about maneuvers. She can use Perform (Dance) for reposition (Dance of Disorienting Shadows) or Sleight of Hand for disarm (Weapon Snatcher). That's quite a boost if you focus on it.
Dirty Fighting is a feat that offers a static +2 to any combat maneuver - but only when flanking. My personal favourite is Surprise Maneuver, basically turning the rogue into a 5/4 BAB class for determination of CMB.
And finally such a feat competes with the ordinary Improved / Greater feats for each maneuver, which provide +2 and an additional benefit.