I always cook in bulk, which is why I prefer to blanche it. I've also fried it which gets you some nice umami on the edges, but unless you want to do it in smaller batches, blanching is less hassle.
Also in the first part, it says that the water/soy sauce mixture will be absorbed into the meat, but in my experience there is still quite a bit of fluid left over. I've tried with no water, but the soy sauce dyes the chicken. My suggestion is to either use light soy sauce and no water, or normal soy sauce with half of the water the recipe suggests.
Either way I've cooked this a lot of times and will continue to do so because it's a core component of my stir fry meal prep. Combine this with some pre-chopped vegetables and some standard "brown" stir fry sauce and you've got yourself a quick, easy, healthy go-to meal.