Whoa, easy with this one.
I would never ask my teacher, Donovan Waite shihan, to show me something at "full-power" or "at speed".
That is just asking for all sorts of hurt, yikes.
Be careful what you wish for, indeed.
... Good luck with this one.
A friend of mine told me about watching Donovan and Claude Berthiaume going at it at high speed and intensity many years ago at a seminar. He said he was happy to only be watching. Considering how injury prone this friend is, that was probably wise.
To go back to the original poster. The question for your sensei is not disrespectful. Just be sure to ask it respectfully. From the tone of your post I would say you should have no trouble managing that. Depending on his skill level and the emphasis he puts on martial training, you may or may not be satisfied with his answer.
My first teacher was Claude Bethiaume, I never felt the need to test his technique. It has always seemed so obvious that he could handle anything I could come up with. However, I have a few aikido friends, some quite a bit higher ranked than me, with which I like to explore these kinds of questions and I try to encourage the lower ranked members of the dojo to "test" me a little from time to time. It helps that we have a free practice period once a week which I usually use to work on jiyu waza. Have had some great fun with former judokas during some of those classes.