Well, unfortunately I can't tell exactly where it came from to go read it or anything, but I see from my Referrer logs that someone linked to Part 3 of the articles on Looting Etiquette I have listed on this site.
Considering there are always discussions coming and going about the whole "Pass on BoP" rule (Bind on Pickup, things you cannot trade once you loot them as they become Soulbound), I'm figuring that's what the pointer was for. If anyone can refer me to the thread to confirm, that'd be cool.
That having been said... I'd like to first explain where those rules came from, and second I'd like to say that personally in the guild dungeon runs I take part in these days, we treat Bind on Pickup blues a little differently than this post suggests, and I'll write a bit about that as well.
(Guild) Rules Come From (Guild) Experiences
The rules were written, originally, before Blizzard put in the update that lengthened the roll timer, and long long before the guild I was in had any kind of voice chat server.
The original roll timer was something like 60 seconds, which is WAY too short when it comes to discussing who should or should not roll on a piece of loot. I mean, if you're all friends and used to running together, that's a different story (to be covered in the next section), but if you're just "well-intentioned guildmates" with a limited understanding of your own class nevermind others, 60 seconds was just way too short.
So, passing on BoP became the rule mainly to allow for actual discussion about who the loot was going to be awarded to in a guild run filled with inexperienced but well-meaning people.
Why Not Master Loot?
Dunno, just seemed excessively controlling, but I'm not sure why we didn't just do that for bosses, and leave it on Group Loot for the rest of the party...
What My Guild Uses Now
The guild I help run nowadays is now uber-casual compared to where it was when those rules were written and implemented in Officer-run parties. We used to be a levelling guild with lots of coming and going and new people to party up with who may or may not be considerate of others when rolling on loot.
Now, however, most of the runs I do have the same 10 or so people involved, and we've been running dungeons for over a year together on our various toons, and exchanging professions favors and the likes for just as long. So, when we hit a dungeon, the "Pass on BoP to talk about it" rule turns into this:
Pass* on things not meant for your class.
Ask before choosing Need** on upgrades.
Designated Enchanter rolls Greed and says "greeding for DE".* If no Enchanter is present, "Pass" can be upgraded to "Greed".
** This is to be polite to your friends, rarely will you be told 'no'.
Also, in my uber-casual guild, we all have alts, so there's a lot of "hey can I roll Need on this (BoE green generally) for my warrior?" and just like the above, it's so rarely met with a negative response that the question is really nothing other than a friendly heads up from a friend that "hey cool, this is useful to me".
Still An Untrusting PuGger
That having all been said, there's no way I'd pass on a BoP in a PuG full of strangers, and I'd be miffed if someone was looking to Need for alts. It's the friendship built up over time that allows that type of "favor" without building resentment that leads to folks winding up marked down on Karma addons or put straight on to /ignore lists!