For what its worth and it isn't worth much.
I was fishing a "swimming pool" clear large pond from the bank. I could see 20 feet out and 10 feet down into the water...it's ridiculously clear. I could see the bass and could not get them to bite on 2 or 3 trips to the pond (cannot remember). I switched from straight braid to braid/floro leader for the heck of it and immediately started catching fish. Now was it the switch, the moon, the weather, the gasoline smell on my hands, were the fish just hungry that day? who knows...but I have used a leader on everything except topwater from that day forward.
Also, I suck at knots but for 2-3 years I have never lost of a fish due to the connecting knot.