He's solo so MOB, with or without engine, is kind of moot. Assuming he is using solar, wind, or something other than propulsion engine for recharge, that could be moot, too.
I was treating your question as a more general one. Obviously a single-handed sailor has different considerations. And, yes, there are other ways to charge the boat's batteries. But, that is what boats with motor often do. Having the charging capacity of an inboard engine also provides one a back-up in case there is trouble with the solar and/or wind generator. These folks
would have been pretty much SOL had they not had an inboard in addition to their solar panels (see their video logs of their trips between Hawai'i and the West Coast).
I don't know the boat, couldn't open the video. But Lapworth design? Might be a beefed-up Cal 30?
It's a Cal 2-30. Not usually considered a "cruising" boat. But, most Cals of that era are pretty solid; and he has beefed this one up quite a bit. At least one Cal 2-27 has circumnavigated. I wouldn't be surprised if a 2-30 has also.
Anyway, in an 8000-mile passage, let's say he carries 50 gallons diesel, uses what, half-gallon to a gallon per hour, it's a few hundred miles, but if he's fortunate with the trades he won't motor much.
So I'm just wondering why he's making "engineless" such a big deal, it's not like it hasn't been done for hundreds of years, and even unintentionally nowadays, when a motor conks out during a passage.
True enough. As I alluded to in an earlier post, many people have done it. However, engines do have advantages (as well as disadvantages). At the very least they provide a bit of redundancy for power generation. But, there have been many folks who have completed long passages w/o an engine. David and Daniel Hays (father and son) sailed down the East Coast, through the Panama Canal, around Cape Horn, and back to New England in a 25 foot engineless Vertue (I can't imagine not being able to get more than 25 feet from my old man for weeks at a time). But, they didn't have any refrigeration, or radar, or SSB, or watermaker, or weatherfax, or lap-top computers, et cetera.