Honestly that kills any interest I'd ever have in this system. It turns a game for friends or compadres you pick up along the way into a job where you play the awful manager.
Doesn't help that trying to sell up FOMO by describing what I missed due to life or some shit happening is one of the quickest ways I'd lose interest in a campaign.
Its not a "system" its a system-independent philosophy/strategy. and its definitely not on 1:1 time bullshit. (though I guess you could run it like that if you hate yourself and your players)
The idea is that the world keeps moving independent of players, the people who attend the session drive the session, and if you do miss a session the only real consequences are 1) You miss out on any loot from previous session and 2) You miss out on driving the adventure. Its meant to be very drop-in, drop-out friendly, but it still requires you have access to enough players to fill out a party for any given session.
And you're letting me pointing out the times the system didn't work reinforce your perception.
The idea of "West March" is that game isn't about mandating attendance, its about getting people to really want to attend a session. Its supposed to be nearly all carrot and almost no stick when getting people to show up on D&D night.
When I say "you need to be able to fire players" I don't mean you fire the player if they miss a session (in fact you AREN'T supposed to do that). What I mean is while it tolerates absences, if its the usual case of three flakes and one or two solid people, West March'ing your game won't save it. If you are player-poor environment while you wouldn't have the ability to fire a player, you probably won't have enough regular attendees.
But if you do need to fire a player, it makes it easier to bring people on board or soft-boil them - try before you buy is much lower risk.
The two times I tried to run it, even if I hadn't been trying to do a "West March" approach, the games would have fallen apart due to too many flakes. I the issue where it was always "drop-out" and there was no reserve bench to tap to fill out the party. There was also no real way for me to jiggle the carrot because it was a bunch of pick-ups who didn't know enough other, so no option to hear about all the cool stuff they missed out on. That was not a flaw in the approach; If I had done this philosophy at the FLGS in college where on "open table" night there were always a few unattached people floating around it would have worked out great; someone can't make it, grab a rando, maybe the Rando becomes a regular.
The forum game that imploded due to drama was sort of poorly run. But it was also a forum game so I sort of get it, where again you had your solid core of 2 people, one mostly steady, and then at least 2 flakers. The DM just filled empty slots with who ever was around. So if you flaked out on a session, he just sent them to back of the queue for invites to fill the roster. And you of course had the issue where people would sign up as alternates and then not be available, so sometimes #4 or or #6 on the invite list would get called up.
which is what lead to the drama spiral where as interest grew, and people who would sign up then fuck off did as well, you had less and less time to respond if a slot was open, which of course got the usual "I WAS IN THE BATHROOM/ANSWERING THE DOOR THIS IS SO UNFAIR. YOU NEED TO DROP SO I CAN PLAY IT WAS MY SLOT." and people who signed up and got slots more and more often didn't want to play the game, they just wanted to do the popular thing. The DM called it quits after not quite a year because all the people bitching about game was more than he cared to manage, as well as all the slapfights, and waning interest - probably due to said drama
The one guy who had a melt down because he missed for "a valid and necessary medical procedure" was just pissed because he had been trying to push for exploring some plot line that only he was interested in. So he missed a couple sessions and when he came back, the people who had attended opted to do something else and they were on the other side of the ocean from the contacts for his Magical Quest. So the sperg had a big bloviation about "I can't believe you'd do this to me, this was a core tenet of my character, blah blah blah" usual sort of tard tantrum when they've been outvoted.