I agree with some of what the author says (building at least one prototype before carving a plan into stone is usually a great idea), but I think affordances for teamwork are missing. The author proudly reiterates how much of their development process exists only locally, with key artifacts like mocks and prototypes being inaccessible to team members. I think one of the most effective ways to increase velocity is to structure your work so that 2-3 other people can work on it with you. I feel like that would be a more productive discussion than some of the nuts and bolts stuff this article dives into (side effects or ifElses or what have you).