There's a reason this is the only forum where this kind of testing is reported. It's been rejected on the more academic forums for good reason. This thread would have been closed or removed on SwordForum or E-budo by now. I leave it here because the standards are intentionally lower here. There are high quality forums you can go to if you want to speak with the folks who have a lot of training under their belt. This is one of the few places where a lot of newer folks hang out with some folks who have some training under their belt.
Tsafa the kind of testing you do is akin to taking a baseball bat and testing it's likeliness to break by picking up rocks of about the right size and hitting them with about 75% of the force that a real baseball player would use. You have no training as a baseball player and so cannot swing the bat properly. The rock is nothing like a ball, so even if you swung it properly the results are tainted, and you aren't swinging it with the kind of force that a real baseball player would use. Then you publish your results, and people who don't know any better assume that the results were done by someone who knows what he's talking about. They take your advice. They use it somewhere approaching it's intended target and force, and it breaks. No big deal with a baseball bat, but a broken sword during tameshigiri can come back to bite you.
Whether you can be held legally responsible or not, there is a certain amount of moral responsibility to at least acknowledge the flaws in your testing scheme.
A note on your "parry" testing, that's a parry like you might get in a stage fight maybe. That's nothing like a real one would look. First of all they wouldn't be flat to flat, it would be edge to flat. Second it wouldn't be one handed tapping. It would be one person with a full on, I'm gonna cut you in half stem to stern I really mean it, cuts.
I wish I had an example video of what I'm talking about. It's not easy to describe. It takes new students a long time to figure out how to cut with hips properly engaged, good tenouchi, and a the proper sinking feeling all of which adds to the power of a cut.
One of these days you're gonna find the breaking point of one of your swords. I fear for you when that happens. As was evidenced in the HSN video, they frequently come back on the user. The only reason that guy escaped serious injury is that he wasn't really striking the table all that hard. If he'd been into a full bodied cut....
Try this video http://www.mounzer.dk/bugei10mb.mov