I am looking for the real world good news ACTUAL experiences which defy gloomy theorists.
Replace "gloomy theorists" with "experienced factualists" and you begin to get a feel for the answer.
If you have two speakers that sound very different then you should have a good enough idea to not need to go to the effort. You'll just go with the better sounding pair.
But if they are close enough you're willing to do the work, then do the work. What you seem to be saying is you're willing to do 90% of the work, getting them into the same room, but not the last 10% that will make the other 90% worth the effort.
Mull that one over. Your answer is in there. Trust me.