Dungeons: leaving after two wipes

Dungeon Finder groups no longer keep throwing themselves at a dungeon: on the second wipe, everyone leaves the group and exits. One group had spent an hour in the Deadmines for 16 deaths and a single boss.

Finding

Deadmines: 30 deaths since noon, all against elites, 14 of them to the first boss; one level 17 to 20 group chained three wipes and sixteen deaths in an hour for one boss out of seven.
Wailing Caverns: 28 deaths, mostly to Druids of the Fang.
Nothing stopped an attempt as long as a monster fell now and then.

Fix

In a Dungeon Finder group (not the showcase group), on the second wipe, once resurrected and out of combat, members leave the group and exit the dungeon. The usual Dungeon Finder penalty prevents landing straight back in the same dungeon.

Other points

False setback: an apparent drop after the previous deployment came from a battleground and two dungeon groups, not from the code; the comparison tool now separates the open world from battlegrounds and dungeons, and flags a skewed comparison.
Gear gifts: ten items sent in an hour and a half; average equipped item level is slowly rising (14.6 to 14.8), mail taking an hour to arrive.

Paired validation on 24 clones: stable indicators, no crash (dungeon groups cannot be reproduced on the test server).