Jonathan_Kaplan wrote:What about stories or anecdotes regarding these trained people *injuring themselves in such a way as their foe doesn't do it for them* in a real duel or in a street fight or a war? Say, messing up to harm themselves due to the pressure? Are there any stories of that happening?
They had a more indirect means of acheiving that end. One was to leave the sword at the altar of the local church and check into the monastery for a while as a lay confraternity.
The other, as was shown when Bernini went after his brother over a argument about a woman, was to run into the church as sanctuary, which wasa more temporary solution. Caravaggio was trying to do the same thing when by trying to get to the Vatican before the Knights of Saint John could get him for attacking one of their men.
Not sure if the boundary stone tradition applied to duels.
Outright wounding oneself or other means to run out of a duel may have been rare. Using Shakespeare as a example of the attitudes of the late period, Mercutio is contemptuous of Romeo for trying to avoid the duel with Tybalt (who'd threatened to kill Romeo, but was Juliets cousin) and so starts a fight with Tybalt as means to reduce his friends dishonor.
In earlier contexts in Njals saga he tries everything he can do to defuse the tensions for his friend Gunnar (Gunnars wife, Hallgerd was prideful and contentious and tried to cause vendettas. Njals wife Bergthora violently opposed Halgerds insults). Gunnar is banished for various killings his wife had provoked, decides not to leave, and is killed. Njals son, kills the man who'd killed Gunnar, which drags Njal into fighting his own vendetta.
Essentially in Njals saga he tries to mitigate the duels and vendettas but despite his efforts ends up dying in the sequence of fights, duels and ambushes. So that saga might indicate how hard it was to actually get out of these situations...at least for the Norse.