I haven't actually experimented with that, but the one accidental experience I had with an LLM seemingly "stressing" (well, predicting text a stressed person would write) makes me guess it's probably counterproductive more often than not: https://news.ycombinator.com/item?id=49163105

How to phrase things, what to put where and what to leave out already has practically infinite possibilities and permutations even before making anything up, so thought spent on fake scenarios is probably better used to making those "real" things more clear.

But then again, the only way to know for sure is to try!