To save you some reading time, the algorithm appears to be: Load the first 10 or so people in alternating rows only (not the same row and not adjacent rows) from rear to front. After they are done, load the next 10 people in alternating rows only from rear to front. Repeat.

This assumes that loading luggage into overhead bins is the biggest time sink for most loading. It maximizes the number of individuals who can be loading overhead compartments at any one time, rather than everyone waiting for the person at the front of the line to load their baggage 1-2 at a time or so.

They go on to state that doing it by blocks rather than strictly alternating may work better for cases of families that cannot be split up.

Ha, you'd lose more time coordinating that than you'd gain. People are really dumb.

I don't see any mention of free-seating, where people are not assigned seat numbers in advance. As this is the method which the cheapest airlines appear to use, where time/cost pressure is at a maximum, I suspect that it does well in practice so I'm disappointed that the author did not consider it.

Southwest captured an entire industry. This was one of the major reasons. That's the difference between "research" and "practice".