I may just invent a query story and send it out just to see what I fish back. What fun.
Please, please don't do this.
Writers complain about agents not responding, or not sending personalised responses, and taking months to respond; and these problems (for writers) have come about because the slush piles are so huge, and so constant; and because writers respond so badly to agents and rejections.
If fewer submissions were sent in, agents would have more time to spend on responding to them. And as most of the submissions I used to get were sent in far too soon--before the writer had adequately polished their work, before the writer had even finished the book, before the writer had done any sort of research on where to send their work, before the writer had developed any understanding of genres, markets, or how publishing works--most of the submissions I got were not things I could even consider, so they all got automatically rejected.
What makes it worse is that I routinely had to work late or take work home, just to get through the amount I had to do.
Why add to that huge amount of work for any agents, when you have nothing positive in mind? It won't be funny to anyone on the receiving end, and it will waste a huge amount of time those agents could spend more usefully on actually helping writers.
Also, there's that thing that is done periodically where a writer or journalist takes a prizewinning book, or a classic, and submits it to a few agents and publishers and then writes an article about how they can't know what they're doing because they rejected or ignored it. But what else can an agent do when faced with an obviously peculiar submission? There are several threads here in which we discuss such stories: you might find them interesting.
We need to put a coffee table book out on our snarky and mean rejections.
There used to be a blog dedicated to them, called (I think) The Rejection Collection. It wasn't pleasant, but Making Light's wonderful Slushkiller was inspired by it. Do check out Slushkiller; it's a great thing.