I disagree, I don't think absorbs any damage, instead, I think it remembers what damage you took during that 4 sec duration, then heals you for it over 6 seconds. What isn't clear to me is when the healing starts. I suspect it's after the 4 seconds.

Temporal shield will essentially undo all the damage you take from Cauterize, and the ability that nearly killed you if you have good timing, but better than that, it's an ability that helps your healers.

No, no, I actually agree. That's what I thought when I read it.

Pop the shield

Take 60,000 damage in 4 seconds...but the shield absorbs it and you don't get hit at all.

For the next 6 seconds, you take 10,000 damage per second. It's like a damage loan...don't worry about it for the time being, but then you gotta make some payments...

I'm with Paul on this one. I think the shield won't absorb any damage at all during it's duration. You'll take the damage but at the end get a HoT that heals you back up for the amount of damage taken during the duration of the shield.
I expect it's possible to die during this if you take too much damage before the healing kicks in. This will be useful if you know you're about to take a large hit that shouldn't kill you.