Good points! It is often not appreciated that with "read offenses" the interior d-line also has time to try to "read" the offensive play. Defensive players are used to recognizing a play e.g. "they are setting up for a screen pass", and then reacting as quickly as possible.
With the b-back hitting so quickly, defenses must have at least one person committed to covering an area (i.e. gap) and since we can block those person(s) from multiple angles, it forces others to react in a split second to the dive as well. It truly forces "assignment football" but with our blocking variations, they must very quickly determine what their exact assignment is on a given play.