Well, I agree with you to some degree that tweaking the injection mapping could change the performance as much as a GOOD header and silencer combo on an otherwise stock motor. By several times? That all depends on the exhaust system. I think that might be a pretty good comparison. The differences are pretty subtle.
I also agree with you that some people call putting a louder can on their bike hot rodding their bike but then a lot of us don't.
But hey! If you can get the surging to go away on surgers without running the things overly rich and get a tad more performance out of them, GREAT! If I buy the stuff to put on peoples bikes, I am going to call it fine tuning their GS. That way they won't come back and say that it is running smoother but other than that they can't tell any difference and they want their money back. It's kind of like when I install an exhaust system that costs a fortune. I warn the customer that despite all the HP claims and whatnot, the biggest noticeable difference is going to be the noise level.