User blog comment:Xilinoc/Ch. 785 - Bullet Bill Luffy/@comment-24.235.56.170-20150507170013

I'm pretty sure the first awakened df we saw was Chopper's Monster Point, although he didn't achieve it in the normal way (whatever that is). Awakened Logia are going to be super interesting to see, but there are a lot of df's that I just can't imagine as awakened, at least not how Doffy explained it. (ie. bari bari no mi, ishi ishi no mi, or basically anything that isn't a transformation type paramecia.)

As for "too much haki", I'm guessing it's sort of like chakra in Naruto. If you do maximum output, then you can't fight as long, so Law was thinking that at that level, he wouldn't be able to finish off Doflamingo. So it's not that there's a world cap, there's just a personal limit before you tire yourself out.

Next chapter (second or third from the end of Dressrosa arc):

Luffy releases Gear Fourth, (probably like a balloon flying around the room) Doffy stumbles forward half-unconscious and tries one final desperate attack, then Luffy ENDS him.

Burgess attacks, Luffy holds his own in Gear Second for a while, but he's too injured to keep it up. Then, before the final blow is struck, Sabo steps in.

The birdcage stops moving, but is still standing, until Zoro uses this week's ultimate attack and cuts it to pieces.

The rest of the chapter is a montage of characters celebrating as Birdcage rains down on them like confetti.