Whedon told the writers to write about the most humilating thing they could remember, the most embarrassing moment, the worst thing they did to someone and put that in a script - then put fangs on it. So the writers would come to the set bowed over and looking a bit queasy.

Could you point the source, please? Because it would be a perfect epigraph to the story I just started writing: Buffy and Spike have to "play" Buffy and Angel in the "Most heartbreaking story of the week" contest led by demon Sweet who abducted Dawn, after all, and will let her go only if her friends win his contest.

As to "quibbling" - my own experience taught me that many people use Internet as a shrink's couch, free of charge. People need to vent their frustrations. Hate posts always reap more comments than love posts.
People just love to write how they hate this or that development, character, twist.