[mariusgmioc]

Hello Jim,

I must observe that "coup de Jarnac" was initially referring to a very skillful and/or unexpected strike, as Jarnac has won the duel by delivering a very skillful blow to his opponent (as far as I remember, it was a blow taught to him by an Italian swords master). Since that blow was previously not known in France, it became named after him.

The negative connotation "coup de Jarnac" we have today appeared later, probably because the exact background context was forgotten.