When it happens, I stop it and tell that we aren’t working for one of the IT consulting companies I hate, and a "you are absolutely right" later we are back on track.

OH MY GOD YES! I actually had it inject synthetic data into my experiments! I had to go back through all my work and re-validate so much to make sure I found all instances of it (it happened in a few different projects).

I now have a system of automated tripwires on all experimental scripts that notifies me and terminates the experiment when any sort of statistical irregularity is detected.