RDF tool seems inconsistent (Lordaeron)

Some friends and I have started leveling on Lordaeron Horde side.

Last night we decidied to do an RDF dungeon, there are 4 of us. 3 dps and a druid. the Druid multi-q'd as tank and healer since we are low level and he can manage all roles.

We expected our queue time to be decently fast since we only needed to find a healer or a tank. But after 25 minutes it never popped. We ended up using /who to find another druid to join our party so we could instant-q. This healer randomly left half way through the dungeon so we just trucked forward with our druid tanking and healing himself as we went. It took us another 18 minutes or so to finish the dungeon and we made absolutely sure we reset the finder tool to try and find us another healer. But it never did, we completed the dungeon as a 4 man time.

An hour after that, I went into the RDF tool by myself as a dps and found a full group within 5 minutes.

Is the RDF tool bugged for groups? is it bugged for multi-q? I'd like to know the rules behind this so I can avoid this issue in the future.

OR, did we just get really unlucky and there was simply no tank/healer in queue for the level 16-21 level bracket? I know that's possible. I just figured it was improbable considering the amount of players I saw in that level bracket when using /who

Thanks!

1. Not many players at your level, and if there are, they might not even queue.
2. Somebody leaving and having to re-queue won't make you first on the queue (I think), but even then, the #1 still applies.

Can't speak for Lordaeron, but on Icecrown the queues seems to be faster once you hit bit higher levels, starting around 20-30.

There's like 30 groups waiting for tank, let's call them A group, 20ish waiting for a tank and a healer, B group, and then the rest are random dps waiting for everything.
If you queue up with just a tank you get into the first group of A group, BUT if you queue up with Tank+DPS for example you don't fit into A group, nor B group, you get dumped down back into random groups of DPS only waiting. Now, your group queued and had all spots filled except for tank or heal, that'll put you down under the A group, probably above B group.
You can test this at level 80 also. If I queue solo as tank it's instant, but if I have a friend healing or dps, I'll end up waiting quite a long time, almost as long as if I queued as DPS alone.

TLDR: There's groups that have been waiting for longer and they're up on top of the queue, hence the name - queue.

Main reason for que pop as single dps is, that ppl que tank + heal. Or other combo. Your druid fills heal/tank slot. Makin infinite que. Its best to que with tank and healer OR 1-3 dps. Not and / or.