Rygar, that post is from 2003 and therefore suspect! Also, I can tell you from being a cleric on live that we don't know jack about the nuances of stamina, especially since clerics and druids both have invigor.
I am doing some video watching now. Here's one where you can actually see the player's stamina depleting with each hit by a visible amount (when he's not running around getting cool camera shots):
https://www.youtube.com/watch?v=ZNbfLOp1mgM
(The video is dated from 2007 but the poster mentions they're old raid videos he found on an old computer. I believe these are all from Luclin.)
You can also see it regens quite fast, though whether that's from buffs or zings I can't really tell. On a raid you can bet that's the first thing they'd buff to high heaven.
Same for his other videos:
https://www.youtube.com/watch?v=q_zqEEHnVmA (Dain, as a monk - really hard to see)
https://www.youtube.com/watch?v=cpaqYUqel1A (Vindi - you can see it pretty well)
https://www.youtube.com/watch?v=4gJ6S-fQEUI (Telkorenar)
https://www.youtube.com/watch?v=jeCpvEpoyn8 (Lendiniaria the Keeper)
https://www.youtube.com/watch?v=ULXGorglosA (Trakanon - toon did a lot of running around, not sure he fought much)