Trying to create hard and fast rules in a highly variable climate is tough. But folks constantly try anyway, so we will always have those who take one or two instances of a particular problem and try to turn it into one of those hard and fast "they all do it" proclamations. And of course in our highly commercialized world there will be those who try to take the premise one more step and convince large numbers of folks to spend money on their solution to this "problem". I find this to be a big part of the Harley market, with more products of dubious value being introduced and hyped than for any other mainline product I can think of. Sure, part of that is created by the many shortcomings of the products as designed and built by Harley, such that folks are eager to find something better. But a large part of it is just preying on those who are easily influenced by others, like the motorcycle mags who print "evaluations or tests" that are basically written by the same folks who make the stuff and buy those full page ads in the same rag. And of course there is that vast store of misinformation posted on all the various Harley related websites, where no one would ever post BS because all Harley riders are virtuous and honest to a fault.
Anyhow, for those who buy into the one size fits all theory, go right ahead and let an occasional case of crosstalk convince you that you have to buy someone else's pipes or someone else's tuning solutions or whatever else someone decides to sell. The fact that most folks would never know the difference doesn't seem to matter to Harley people. One guy claims to have "fixed" a problem on his bike by adding some whizbang device, so other's who have never experienced the problem run right out to buy that same device. And of course after they do so they have to justify the expense in their minds, so they are quick to proclaim on sites like this one how great the results were. The fact that they didn't have the problem to begin with tends to get glossed over.
What it comes down to is, if you feel the need to spend money on stuff you don't need, and that money isn't being taken from your child support payments or being stolen from someone else, do what you want. That's what keeps our economy rolling along, lots of mindless spending.
Jerry