It came to my attention that Rob, together with a Van Essen, had a while ago ran some jousts in 13th century armor (mail + tunic) with some surprising results for many I suppose

Though what I didn't catch from that was if they actually took any hits to the mail directly with the lances. I don't know if Rod is active (or if he is, where I can reach him) so I am asking here if anyone knows whether they hit the mail with the lances directly, or not.

Perhaps this is also the right place to ask for clarification on Dan Howard's maille article, which indicates that 12th Century tournaments used sharp (no rebated) lances.

I tried to start a discussion on this point elsewhere, but couldn't find anyone who had sources for the weapons used in earlier melee-style tournaments.

In the 14th century jousts described by Froissart, they were still using sharp lances, so the change to rebated ones occurred after that time.

Best to read it for yourself.
https://ehistory.osu.edu/books/froissart