Parts life vs rating
Bumpfoh -
This may well be true for CFM56 - can't say for sure.
However I know that 747SR (high density seating, lower fuel load, optimized for high cycle short range ops) had its engines de-rated something like 10%. JAL and ANA were big customers. The fallout from this type of ops was extended parts life. I don't think there's any reason this shouldn't extend to the CFM56.