Meaningless? I was around .52 originally and now I'm closer to .68. I can tell a difference in the roll off. The .52 isn't as "smooth" as the other. The lower was very clean but it didn't carry a roll off which made majority of drums and bass unrealistic.
That was my experience with my speakers tho :/ I guess it's different with everybody. I can see how .5 makes closer to 20hz much cleaner. I did like that aspect. Double kick was much cleaner too.