Now, the ram rule engages when a ship ends its movement intersecting another ship's base. And it is has been made quite clear a sequence of rams (i.e. each time you slow, you hit a different ship) only interacts with the ship hit originally, and the moving ship. (Feel free to correct that if I'm wrong, but I'm pretty sure I understand it.) Now, in the event that a starship (the exact example is an Imperial-class Star Destroyer) intersects multiple ships on the end of its move (in this particular case a pair of Neb-Bs in close formation), how does damage delivery work? Obviously the ISD takes at least one hit, but does it take two and each of the frigates one each, or does someone semi-arbitrarily choose one frigate to "be hit first"? Empirically one frigate is closer to the ISD, we know, but in this case they were within Mk 1 Eyeball PME (Probable Margin of Error) of each other. Can anyone clear this up?

PS And in case anyone was wondering the Star Destroyer flew away; the frigates did not.

Only the closest is hit, and there is an entry in the FAQ (I believe) that answers how to determine it.

As (allmost) allways, Drasnighta has it right. Even the part about it being in the FAQ. I must say though... I realy didn't think an FAQ entry was neccessary to tell us how to compare two different measurements, but there it is...

Q: When a ship overlaps more than one ship, how does a player determine which of those ships is closest?

A: The player measures range to the overlapped ship that appears to be closer and temporarily marks that measurement (such as by holding his or her thumbnail where the ruler reaches the overlapped ship). Retaining that measurement, he or she measures range to the other overlapped ship. If the second range measurement is beyond the marked measurement, the first ship is closer; otherwise, the second ship is closer.

I posted my answer immediately last night before passing out from a mixture of total exhaustion and 2-Year-Old Menace, so I did miss a point...

It is listed there, but if there's no way to actually determine who is closer, if they are equidistant , then it will most likely have to be arbitrarily decided... There's no specific guidance in that regard... So at which point, you have three choices:

1) The Player with Initiative decides, as its something that affects both people in a way, and therefore, that's the only 'decision breaker'.

2) The Player who owns the frigates decides, in the manner of "These things happen simultaniously, and therefore, I can choose the order"

3) Completely Randomise it.

Lets say the star destroyer is a perfect equal distance of both Nebulons. If you use a click on the joint belonging to the speed the ship is moving (and which is the overlapping part) you would overlap one ship more than the other. By starting such a turn in "real life" you would hit the one you'd overlap more, first. I would say as moving player, this click would give you choice which ship you'd hit first.

Any thoughts?

You could potentially use that real-world concept as a flavour device towards finding a solution, yes.

But it is another argument that you would have to use to convince someone, rather than having a rule to spell it out.