I don't see how an effect being called puissance or tenacity is any different from a phylactery of "fortitude".

If you test a prep sensibly you are usually ok.

For example, two of us tested out a prep that had a side effect called Malaise. I tested it in a place where I was confident I would be safe if I suffered an ill effect. The other guy tested it at the entrance to the sylvan grove, and he was a defiler. Needless to say, he died as a result.