Bladt knows that at this point in the season he cannot change what he has been coaching the players since day 1. Not to mention, I would guess that a traditional power like Harlan has been teaching this defense for years.
If Harlan has practiced and played a head up, 2 gap front all season then changing the techniques would result in far more issues than getting worked by a bigger line. A better approach would be to rotate more players that have practiced the same scheme all year. Switching to a gap control front with 10+ weeks of two gapping would result in some big time breakdowns when a kid doesn't play his shade. Lastly, if Harlan plays that front then they should be thankful that they did not play Pella because I've seen their Tight Slot and Wing looks. They would reach Harlan's 5s/8s (or fold them), seal (or pin) their backers and it would be off to the races. Not to mention what they can do with motion. A 43 is a great front but when the QB can run then you better have some safeties that enjoy partying too.
JB