From two articles:
The first one proves Mangini is all about disguise more than he is about just stopping the play post snap. The second one puts him in Harbaugh too complicated status.
1.
Mangini: "If good quarterbacks know what you're in, there's always something in a pattern that can beat that coverage," Mangini said. "So I'm a big believer in making an offense make post-snap decisions, so that they have to react."
2.
http://blogs.mercurynews.com/49ers/2015/08/18/eric-mangini-describes-how-49ers-defensive-staff-communicates-on-game-days/
Allow defensive coordinator Eric Mangini to explain:
"I'll get the personnel from, Mick Lombardi (defensive assistant) did it this weekend with Jason Tarver (senior defensive assistant/linebacker) in the booth and E.J. (Ejiro Evero, defensive assistant) as well. Mick is giving me the personnel, Jason will confirm that and also talk about down and distance. They'll both be looking at substitutions.
"That comes down to me. I'll make the call into the players. Clancy (Pendergast, linebackers coach) and Tim (Lewis, secondary coach) both work on personnel, getting the right guys in and out.
"After the play, everybody is tied into a different personnel. Jason works the front seven. I can work with the front seven or back end. Up in the booth, Mick's been working with the secondary, E.J.'s been working with the linebackers. Each position is covered up top, and below.
"It's a little bit like air traffic control."