I just had a session where I fought Andariel and she went into her invulnerable phase with the three pillars and the spinning beam. I killed the pillars and she didn’t come back. Just kept summoning spirits and the beam. I waited and then used my only scroll of escape.
Then later I fought the Beast in the Ice and he got stuck in the ice lanes phase. No scrolls of escape left, so I hit alt-F4. Logged back in and somehow my character is still alive.
But this would have been a really crappy way to lose a HC character. Please fix the bugs and consider increasing the Scroll of Escape drop rate. They are a good anti-bug, anti-lag death fix.