death/heal glitch?

[sixteenmiles]

not trying to snitch on a dude; i can't even remember his name, but i was grouped with this guy in crushbone yesterday when a pull got hairy and in the group chat i was typing

"dude run"
"dude"
"run"
"run for the zone"
"wtf"
"dude wtf"

and this guy was just holding the line, beating down on this red con and not winning. this thing beat this guy to death. i watched his health bar drain down to zero. i even watched him keel over dead on the floor, and then right on that tick where he keeled over dead on the floor he just zipped back up to standing and his health bar went up to 100%.

and the dude didn't say anything about it and just carried on beating down this mob, and when we killed it he didn't say anything. just moved on to the next mob. and i said to him "dude, wtf just happened?" because it was just the two of us and neither of us were healers. and this guy just says one word.

"glitch"

now... maybe. but on a scale of 1 to suspicious this guy had my scale tweaking. so just to satisfy my curiosity, is this a known glitch, or was this guy messing me around?