MaximRecoil .
I'm not bothering to go through that word salad of rationalizations of why you have absolutely no argument, but just to spell out why your whole thing is a complete logic fail.
This all started when you made the statement that you cannot get the same workout on a light bike as you do on a heavier bike. That statement was never qualified in any way. It was postulated as an absolute truth. When it's pointed out that there's several things you can do that actually equalize the workouts you get on unequal weight bikes, you announce that for the sake of the argument we're going to assume you can't do those things. So essentially, you're conceding that in the real world, you can actually get the same workout on the two bikes, but in a hypothetical "all other things being equal" world, you can't. Why in wide world of sports would anyone care about that hypothetical world?
Keep in mind, your original statement was about "workouts", not "work". Discussing the quality of workouts without discussing effort is a pretty weird thing to do, almost as weird as discussing the work involved in propelling a bicycle without including the weight of the rider.
So, basically, you're now arguing that if we assume you can't make any other changes to the bicycle or your effort, you can't get the same workout on two bikes of different weights.
Congrats, Captain Obvious!
I get that you want us all to go through why your little quibbles are wrong, but I know when someone is trying to put up the shiny objects to distract from the main issue, which is your basic point is nothing anyone would or should care about.
By the way, if you don't think your refusal to define "significant difference" isn't a tell, you really have no business trying to argue logic.