I don't totally follow his methodology for "time-boxing", it seems like goal-setting with a time for evaluation and course-correction, which is something all goals should involve anyway.

Time-boxing as I've heard and used it before is a working style, similar to a scrum sprint, where you have a set of goals and a limited set of time, so you force yourself and team to prioritize what fits. The team then constantly re-evaluates what fits and takes a hard realistic look at the goals that have to be done at the end of the time-box vs. those that can be changed/cut.