fluorocarbon vs. mono: Does it really matter?

[animal]

I have fished side by side with a buddy(a buddy who always outfishes everyone),exact same lure,exact same presentation,me with mono,him with flouro.The flouro leader was tied direct,the mono used a snap.I was outfished badly.
After switching rods,the tables turned.
Flouro is also non-porous,and doesn't absorb water.Mono,on the other hand can lose up to 15 % of it's breaking strength when saturated.
The only time I don't think it matters is with live bait,however I still use it.The deal is,it's an advantage,not a gimmick.With all the time and money I put into fishing,I'll take every advantage I can get.