i've seen and had that experience many times except...
-when i was the only cleric with revive people kept on spamming "REZ PLZ", told them i'm not gonna rez them if they keep spamming plus the cool down is long, but it didn't stop them from spamming it... then i got told to F*** off by the tanker cause i was reviving the fighters who died (he was supported by 2 lvl 17-19 clerics) this one ended well when only the clerics were alive and i tanked the last marlone.
-once only one cleric with rez, my fighter and an archer on the last boss, a whole lotta people sucided before real marlone and mara after abusing the cleric, we ended up winning with time to spare
seems to happen alot in Mara KQ, cause in gold hill and robo everyone wasn't spamming for heals and revives.
also with the Mara kq's i've been in people lost heart when a mage or archer tanked, which was sad cause the archer or mage had loads more def then the fighters.