The last two years I have really gotten into experimenting with flurocarbon leaders. I started doing it at Lake Geneva when I noticed that I was not getting bit as much as my partners that were using straight mono. I switched it up and started doing really well with it. I started with P-line, but I did not like the knot strength and ended up using gamma, which I was impressed with. This was for deep water live bait fishing.
This year I started doing it even more after again noticing in the late summer and fall that the guy in the back of the boat was getting more bites on mono when we were finesse fishing. I started using the fluro leader for that too and my bite ratio increased dramatically. For some reason I have not had to adapt this in the early spring or summer. The fish seem to hit all the same. Who knows though, I may have even had better days if I would of tried it. I really used to laugh at the notion and think of it as a waste of time until I saw the difference in front of my own eyes.
I tie the blood knot for finesse fishing which can be time consuming. The knot strength is very good though and the transition point is all but invisible. There are other knots that work, but that is the one I am most comfortable with.