In which school of swordmanship have you enough knowledge, so I get the context of your previous statement " it's already clear that the anti-tsuba forces don't consider the behavior of actual swords relevant to their practice" ?
My God, did this thread really end up as a for and anti tsuba argument? That's as mind numbingly trivial as the old "Certs is a breath mint. No, Certs is a candy mint." commercials.
I think one can easily figure out where one might stand on this issue... For me, the very first time I had a solid oak tsuba break in two and fly across the dojo, my stand on the issue was a done deal. No tsuba, those were my knuckles that would have been clobbered.
The idea that you get wedded to one idea or the other as a reflection of your superior or not adequate technique is ridiculous. Going back as far as you want, different koryu had different preferences for their bokken and shinai. However, no one, to my knowledge had a live blade without a tsuba. The tsuba clearly had a function. Not having one changes how you have to run your technique. Since real swords have tsuba, I go with my practice weapons having tsuba. You don't want to use one, that's your business. As far as my teacher, Saotome Sensei is concerned, you want to protect your hand or not is entirely up to you.