Questionable Gang Plank W

Tried out 2 matches with him sine he has returned, but I seem to be a little suspicious of the W.

I try to use it to get out of crowd control I feel like half the time I lose out on any health I was suppose to gain, is there something I don't know about like if you get knocked up or something while using W you don't get health?

I could be wrong but from the 2 40+ minute matches it's what I have observed. I'll keep playing to see if I can prove myself wrong