Sadly I can't tell if this is a joke or not because I have met so many people who seriously believe things like this work. They are the ones who eventually get the most pissed when LLM messes up on them because they got the LLM to "promise" not to do the specific thing it ends up doing.
They generally evolve their superstitious ritual to something else that will eventually fail, like changing the wording, or making the LLM specifically include a phrase indicating a promise of quality. They also believe when the LLM "apologizes" and think that indicated self reflection and learning. Very few are prepared to accept that the LLM can go off the rails at unpredictable times and unpredictable circumstances, and their utility has to be monitored like a hawk unless the outcome really doesn't matter.
Well auto fellating is the trademark tone of LLM output, which the email probably is.