Clarifying the Champions League tie-breaking rules

So Uefa Champions League Group F, the infamous Group of Death, is in a bit of a muddle right now. Napoli beat Dortmund. Arsenal beat Napoli. Dortmund beat Arsenal. Everyone beat Olympique Marseille. That leaves a three-way tie for first, with everyone on six points except the Frenchmen, who are down with zero points, waving madly and yelling "Hey guys! Throw us a rope down here, will ya?"

During the Marseille-Napoli match, it seemed much of Twitter was confused as to the way tiebreakers work in the Champions League group stages. "It's goal difference," some said. "No, it's goals scored," other said. "Away goals matter," was a common refrain.

I can see how it might be confusing, as Uefa has hidden the Champions League rules and regulations deep on their site, and even if you can find the document, it's not exactly the easiest piece to understand. Let's work through it:

1) higher number of points obtained in the group matches played among the teams in question;

• Hint: that's three points each for Napoli, Arsenal and Dortmund right now. Next!

2) superior goal difference from the group matches played among the teams in question;

• Hint: Arsenal have +2 from the 2-0 over Napoli, yet -1 from the 2-1 loss to Dortmund. I'd guess that puts them at +1. Dortmund have a 2-1 win and a 2-1 loss, so they're at 0. Napoli have the +1 from the BVB match but --2 from Arsenal, putting them at -1 and leaving us with the current standings: Arsenal -- Dortmund -- Napoli

But things could get more complicated by the end of the final three matches. Should two or more teams be even on goal difference, what comes next?

3) higher number of goals scored in the group matches played among the teams in question;

• Hint: Arsenal and Dortmund even on three, while Napoli have just one

Come on now, doesn't away goals factor in somewhere?

4) higher number of goals scored away from home in the group matches played among the teams in question;

• Hint: Dortmund have three, Arsenal and Napoli have zero

But then Uefa throws us a curveball:

5) if, after having applied criteria a) to d), teams still have an equal ranking, criteria a) to d) are reapplied exclusively to the matches between the teams in question to determine their final rankings. If this procedure does not lead to a decision, criteria f) to h) apply;

Say what now? Is that not what we just did? Applied those rules to the "teams in question"? I thought, perhaps, I'd read something wrong and Uefa meant all members of the specified group, rather than the three even on points. But that doesn't make sense either:

6) superior goal difference from all group matches played;

Ok, that means we include Marseille now, right? Not before? So what's with rule number five? And why is this room spinning?

There's only one solution to this mess: Either Arsenal, Dortmund, or Napoli is going to have to throw themselves on the sword, sacrificing themselves for the greater good. Otherwise, some poor Uefa dude is going to need to be locked up by the nice men in white coats after he's done trying to determine who moves on to the knockout round.