Would it be broken?

[Lord Ruby34]

If I let most melee PrC's advance maneuvers known, readied, etc. For this particular case I'm looking at Iaijutsu Master for a bardblade. I don't see anything horribly wrong with making Melee more powerful but I'd like to avoid any pitfalls that I might have missed.

[Yora]

Many of the older PrCs ae terrible, as they have basically no class features worth mentioning. A Prestige class that advances maneuvers at each levels and has the class features of Iaijutsu Master still would look pretty boring and weak.

[Lord Ruby34]

Eh, I was going to suggest five levels to him, to take advantage of his really high CHA score.

[Metahuman1]

More then half the Melee 3.0/3.5 Melee oriented PrC's are in the "sub-par too stink on ice" category. You aren't gonna break them with this, trust me.

[Lord Ruby34]

Yeah, I was more worried about the other half that didn't suck. Like dervish or warshaper, but I guess if someone wants to sink half their feats into taking advantage of Dervish I shouldn't stop them. And warshaper isn't wholly melee so...

[Lateral]

On a case-by-case basis, sure, go ahead. There are some classes where this might be a bad idea, though. (Say, War Hulk. Lack of decent iteratives matters a lot less when you're using standard action maneuvers most of the time, and the class is crazy powerful as is.)