Optimal boarding method for airline passengers

This has been one of my open tabs for a while now and I finally got around to reading it. It's a research study on how to best board airline passengers. Despite popular wisdom, back to front is not all the much faster than front to back (even though probably 50% of airlines go for some variation on this method). The key time consumer, as the paper explains, is the amount of time it takes for passengers to load their luggage. Therefore, back to front gets clogged with people waiting to put luggage away. The paper suggests the key is to properly space people so the most people are loading luggage at the same time. Very interesting.