My personal experience is that the limited amount of benefit yielded by short fletches, does not out weight the known benefits of the maximum fletching for hunting situations.
I hunt 4 fletch 4" or even 4 fletch 5", and even some 3 fletch high back bananas (big ol' suckers!). I have messed around with 4 fletch 3" and had no issues ...but...I like the confidence of KNOWING I have plenty of feather to compensate for any issues I may encounter while hunting.
The speed gain is negligible - may 1 or 2 fps which will not affect anything. Let's face it, deer have been scientifically proven to have the ability to duck a compound arrow at well over 300 fps if alert. So us shooting 150 - 190 fps won't have an impact if we gain 1 or 2 fps.
And lastly - I really like the look of the bigger fletching. I don't want my arrows to look like my compound arrows did all those years ago. I've even tried a shaft with blazer vanes on some of my recurves with elevated rests and they shot great. Just can't stand the look of them.
I would never give someone grief for shooting the short fletching or blazers, but for me - I like a lot of feather back there, even though all of my set ups have been bare shaft tuned.