Re: Why no tsuba?
YouTube is full of footage of accidents with katana, with results too graphic to post here. It usually starts with some unqualified person or group playing around, wearing hakama and swinging bokken, then some newbie feels entitled to use a real sword to do some "iai" or whatnot... and ugliness ensues. Even if you stick to wooden swords there's the possibility of serious injury if you don't know what you're doing. Something to consider.