In my opinion, Fluro requires more of a load to cause that stretch though (it doesn't stretch under the light tug of a fish so it acts like a no stretch line in that situation) and because it doesn't float up (I've seen mono bowing upwards towards the surface and I think the fluro goes to the bait with a slight downward belly), I think you have a straighter line to the bait. Regardless of the particulars, I KNOW fluro is a lot more sensitive than mono or copoly. I had a day with two identical jigs, on equivalent rods with equivalent diameter lines. I could feel the bites on the fluro rod; I could not feel the bites on the mono rod. I caught 22 fish that day. It was 20 on fluro and 2 on mono so I think you can feel more bites with it. Because iof the extra expense, I didn't want fluro to be better, it just is. I didn't want to spend the extra money for it, but it is a better product and I want to fish with the better product.
I feel like I get better hooksets with fluro than mono too , but that is harder to explain. I seem to get to the fish quicker (less belly in the line?) and I can feel the fish load in the rod before the fluro starts to stretch a little.
Fluro is said to be a lot less visible to the fish. I really don't care about this in my bass fishing. I do care about it for my fly fishing leader material. I use fluro for leader material on my nymphs and a non fluro for my dry fly offerings.
I've yet to have anyone explain why I should be using fluro for leader material on my braid or nanofil spinning rod setups. I've said I am not concerned about visibility. I don't think that abrasion resistence is gonna be great on those light lines (6.8, 10 lb) anyway. The short length of leader renders a lack of stretch in the leader less important that the stretch in a main line. To me, fluro is picky about how it is tied(more prone to knot failure), it is more expensive than a quality mono or copoly, and has a larger diameter than equal strength mono which affects how the finesse bait behaves. So someone PLEASE make the case for fluro as that bass leader.
I can see in the future me setting up a Ned rod with 6 lb Invis X for windy days. I would do it now , but money is a little tight.