The simple answer to your question....in 2019...for an UL rod there is no difference in sensitivity between a 1 piece or 2 piece rod....and with the advent of the spigot ferrule the advantage single piece rods may have had in the bending curve vanished. I’ve owned several high end UL rods from Loomis and Phenix......2 piece and 1 piece....I could tell no difference at all between the 1 piece and 2 piece Phenix Elixir or the 1 and 2 piece Loomis trout rods. Now this subject can often open up a can of worms. If you went back many years ago you could see the difference in the bend of a 1 piece vs 2 piece.....but those days are gone.
Regards
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