Here is my problem:
If you put yourself in a position to test any one's abilities, then you first must be saying in yourself that you are "in a position" to be testing. Thus you think yourself better, or of greater knowledge than the one being tested.
I disagree. It's a presumption to think that because someone wants to experiment/test something specific that the person automatically assumes they're in a better position to judge. I think the gist of what the OP is saying is that experimentation is the backbone of learning. It's no different, as far as I can tell, than ki tests.
It's analogous to expressing ideas here on Aikiweb: I put forth whatever is on my mind to see what I get in response. Just because I say "I think this or that" doesn't mean I assume I am right...largely because I respect my own ignorance (certainly I'm better sometimes more than others at displaying that
). Similarly, if my training partner and I have an understanding about what we're doing (hence the mention of "ask"-ing in the OP), I should be able to try things like being unmoveable or otherwise gripping in different ways.
The problem comes when our partner doesn't know what we're trying to do or doesn't agree that that is the appropriate time to try it out. If we resist technique during demonstration, as but one obvious example, our partner may quit the process altogether rather than find a solution to the experiment, and we might be left thinking "oh he couldn't do it."
And, personally, I would say it's always
a case of the blind leading the blind; it's just that we're all blind in different ways and to different extents. We learn to "see" by feeling our way around, usually bumping into things unexpectedly, and tracking the experience in order to find our best approximation of the Way(s) of things.