If you've been following the top guilds and the World First races in WoW, you'll notice that a lot of the top guilds have been calling it quits. I think the higher-than-normal burnout has two intertwined causes, and it's hard to propose solutions without understanding those causes.
First, I don't think the long hours during the race itself is an issue. The world-first guilds have always raided intensely during the first couple of weeks. Ciderhelm talked about it in his guide to Time Management way back in Vanilla/TBC. You raid intensely for two week, and then have a very relaxed schedule for the next four or five months.
The current issue facing edge guilds is that to be competitive, each raider needs multiple "finished" characters.
First, the multiple part. Edge raiders need multiple characters for split runs as well as to swap characters around to have an optimal setup. There's always been a degree of this in WoW, but the number of characters needed has steadily increased. I believe that edge raiders are now expected to have four or five characters they can switch to for progression.
Second, the "finished" part. A finished character is one which is fully geared and maximized from the previous tier. This is the major change in Legion. Before Legion, it was fairly easy to finish a character, especially if you were in a guild which regularly cleared Mythics.
But Legion increased the amount of work to finish a character significantly. Now you need Best-in-Slot legendaries, maximized Artifact Power, and Warforged/Titanforged gear to be truly finished.
Now, this is actually great for those of us who play one main character and aren't at the cutting edge. There's always the chance of upgrading. Maybe you'll get a titanforged piece, or a new Legendary. I've only got 40-something points in my Artifact Weapon, so more AP is always useful.
However, for the edge raider, this is murderous. Where Ciderhelm once touted a intense two weeks, then a relaxed schedule for 4 months, the modern edge raider spends all her time trying to finish her character, chain-running content for AP and the chance of titanforged gear. And due to the first requirement of needing multiple characters, she has to do this on four or five characters. No wonder they are burning out.
The big problem, of course, is that the longer path to finishing a character is excellent and enjoyable for the vast majority of the population, even if it is burning out the edge raiders.
In the next post, we will look at potential solutions.