Hmmmm. There are some things there that I like and, some things I'm not so sure about.
First, I'll say that I think he seasoned it very nicely to start off with. So many people don't understand that a big cut like a full packer-trimmed brisket requires a LOT of seasoning, instead they treat it like a steak and on too many videos I see, they just lightly sprinkle with salt and not nearly enough black pepper. Not only will it NOT have enough seasoning flavor, but it won't set up for a good bark.
Next, I'll admit that I don't know anything about cooking with electric smokers, but there are places around town that do it, and in general I find their products to be inferior to the joints that use real wood smokers, traditionally offset stick-burners. You're not going to find many (any?) joints using electric pellet smokers, in Texas Monthly's Top 50.
Back to the cook-- the first 6 hours of his "4-2-10", I'm okay with. I don't actually think it's necessary to change temp partway through, in fact these days I go at 285-300 for all of it. But it's fine, 6 hours at a combined 225-275, should work out no problem, as your starting steps.
But that's when things get a little wonky, in that final 10 hours. I don't really have an issue with that as a "holding" step but the problem is, I suspect he's converting from cooking to holding, too soon. He doesn't ever show the final internal temp, but he drops the cooking temp after those first 6 hours, down to a point that's so low that it's not going to be rendering fat nor is it going to be converting collagen to gelatin. And I can tell from the cross section that the fat isn't fully rendered, and I can tell from his slice that there is way too much pull. It should just flake away with minimal effort, but he has to tug on it pretty good in order to get it to come apart. Also, his slices are too thick, but that's just technique and not related to the cook.
Oh, and finally, that "steaming" he does, where he adds water. That's just going to ruin the bark on the bottom of the brisket and make it really soggy. The whole point of wrapping in butcher paper, is that it helps the brisket hold temp and retain moisture, but still allows the brisket to breathe, so the bark will set up, all the way around. Putting it in a foil boat with added water runs completely counter to the purpose of wrapping with paper. He didn't show it but there's no way the bottom of that brisket is anything other than a gooey mess, sitting directly in a water boat like that.
Anyway, there's a lot of ways to get this job done, and I think some people just work too hard to make it more complicated than it needs to be.
Personally I do a heavily seasoned packer at 285-300 for as long as it takes (probably around 7-8 hours for a 12-13 lber), and I don't ever wrap on the cooker, and the final internal temp should end up somewhere between 197 to 205 but it's irrelevant because what I'm actually looking for when I probe, is that it probes like buttah. Then I throw it in a cooler with a loose wrap of paper for anywhere between 45 minutes and a couple of hours. Throw it on the cutting board, slice, and voila!