Broken is a bad term that people (myself included) have thrown around with stats too much. Right now, from various community tests, parsing, etc. here is what I have uncovered for knowledge as far as melee stats are concerned:

DEX: No affect on Accuracy, very slight boost to Critical Hit
STR: Increases Attack with very large diminishing returns, you won't notice a change 20-30, 30-40, 40-50, etc. You can only see a substantial difference when going from, say... 60 STR to 120 STR.
VIT: HP Box magnifier.
MND: MP Box magnifier (as much as people like to think this isn't for DD, when it comes to this game, having a deep MP pool is not a bad option for any class).
PTY: Helps WS DoTs stick better (Skull Sunder, Bloodletter, etc.)

So, since you get SO many points to pump out, and SO little visible different, people consider them "broken."

They work, poorly, and not as intended, and it's getting changed. After physical level is abolished we will have less points to re-distribute & they will have a larger impact per point. I think they're aiming to make stat changes very noticeable.