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.
Like I've stated before, I see no issue with Aikidoka of the same peer giving good spirited challenge to one another, I agree the benefit it gives to growth. This is a point I think you and I are in complete agreement of!
Experimenting is different than testing some one IMO.
My issue comes with the concept of "testing". The OP gave forth a scenario where one could judge the extent of another by simply grabbing them then gauging their response. My opinion is that only some one who ,in honesty, is of greater experience than you can gauge the abilities of others in this way accurately. Otherwise, under the scenario put forth by the OP, how are we to determine or judge that a successful throw is the success of the nage, or the failure of the person who is doing the testing?
If you agree we are the blind leading the blind in many respects, then it is impossible for us to gauge each other accurately. Thus, IMO, we should just train and learn, without setting up scenarios in which we can judge our classmates, but continue to judge ourselves. Also, we should allow our instructors to keep tab on our progress and tell us when we are lacking and how to fix it along the way.
Again, I'm in agreement with you on the subject of good-spirited challenges. But the results of which are for each person to take away from with a grain of salt about themselves, to develop themselves. I don't consider good-spirited challenges as a means to judge each other, but yourself.