I think that would depend on whether your joke is clear enough that a reasonable person would not think it “materially misrepresented” your experience – if my review of a Python book says I learned how to import antigravity and was now flying around the neighborhood, it’s probably safe because readers would know that’s impossible. If my joke is too subtle or obscure, it’s probably better not to have it because it will likely confuse people who don’t recognize it.
