RD 17 you are my new hero!!! You definately know what you are talking about in reference to bubble screen and tunnel screen regarding blocking, design, and intent! Fun to read replies that have solid football explanations.
As for the person who mentioned that they could call the play based on the formation---this is highly improbable. You can't just predict that it's going to be a running play or a passing play. If you truly know what play is coming you would be able to predict the blocking scheme also. The "run over left guard" could actually be a number of running plays (i.e. power, isoloation, zone, trap, or counter). Each of these running plays have different philosophies on how to create a running lane. Some plays are better versus certain types of defenses than others. So maybe if UND seems to be running the same play it is for a perfectly logical reason---it fits versus the type of defense they see, takes advantage of a mismatch on the line, or perhaps it is simply the RB's or O-Line's favorite running play. Plus, they could run the same play (zone) but "tweak" their blocking rules based on a stunt/blitz that has given them problems.
Sorry, little venting there. I just don't see any reason to second guess someone who has lead an offense to the highest rating in the conference for 2 out of the last three years and usually has the QB with the highest rating in the conference. If you are leading the league in scoring and have the highest QB rating you can't really argue.