I was on a long ride and we stopped for lunch. Someone found out I built my frame (back in the '70s), and asked what tube thickness it was. I have no idea. I think it's probably around 9/6/9 or 8/5/8 (except in gauge thicknesses because '70s).
He told me it was irresponsible for a framebuilder to not know what the tube thicknesses are. I told him after he builds as many frames as I have to get back to me.
I wouldn't mind building a pile of frames changing one little thing on each of them to see what the differences are, but, in the absence of that much money and time, I find that confirmation bias works pretty well. Tell me how you want it to ride and the tubes you want to use and I'll convince you that your tube set gives that to you. Yes, I'm a horrible marketer