This was addressed in the article. It states "The outcome is fairly robust in the sense that it's relatively insensitive to deviations from it, say, because of couples or families being seated together." During ticket purchase, families could be noted as such and all given the lowest group number amongst them.
Traveling Ryanair or other budget airlines, you get a "sequence number" which is the order in which you've checked in, theoretically this is also the order in which you board (seating is unassigned). But then you get there and they say "families traveling with children board first" and as this is an Irish airlines that's, umm, everyone but me. Which is understandable perhaps if people want to sit together, but hey, didn't I pay for my ticket too? So if you're going to have a free for all then do that, don't sneak in seating policies by the back door!
The good news is that exit rows are desirable, and children and their keepers are prohibited (in the US, anyway) from sitting in them. So they can pre-board all they want, and not take away any of the good seats.
(Of course, people are idiots. The one time I flew Southwest, I was on standby and boarded last -- the only remaining seat was an exit row. I was amazed.)
I recently flew Southwest and sat in an exit row. The flight attendant came by to give her spiel, and the 100 pound young woman sitting next to me expressed doubt that she could lift 50 pounds. I think it took about 5 minutes of pleading(!) with the rest of the completely full plane to find a volunteer to change seats with her.
shush... please don't reveal this well guarded secret... I love always coming late in the plane and still getting the exit row.
But if you start teaching other people that those are nice sits....
