By all accounts, Manny is a good husband and father and a likable guy. I wish him well and think that he actually might be able to convalesce his career at least to the Shannon level of still getting some assistant and DC jobs. Maybe more.
The bottomline with his HCing is - he just may not have the DNA to be the head guy of a major college football team.
The one thing he has going for him is that he always seemed to figure out what was wrong and come up with a plan to fix it, but always too late or later than it should happen. So, he's not a dumb guy and I really think he screwed up by not taking the Temple job, but of course, if I were in his shoes, I would've done the same thing and accepted the UM position. Long term, Temple is what he needed to learn the position.
Adding to the bottomline - successful HCing involves a lot of different things and he definitely had some of those tools, but there are certain intangibles that he has not demonstrated yet and looking at the big picture, those non-quantifiable intangibles, or lack thereof, is what cost him his job.
He lacked the ability to create toughness in the players.
He couldn't make them accountable to the level required. Also, he meddled and was too insecure to NOT be the "Smartest guy in the room." I currently work with someone who always has to be the "Smartest guy in the room" and it's stating to wear on some important business relationships that we need. Point is, he wasn't confident enough to hire excellent people (Zo for instance) and let them do their jobs.
Again, he is not dumb and always showed the ability to analyze, evaluate and make changes (usually too slowly) once the live bullets were gone and the heat of a situation had subsided. For his own good, I hope that he realizes that his failure did not come from misevaluating LBer recruits or some X'O's concept.
His failure came from a mixture of some character flaws and, to this point, lack of certain leadership qualities required to be a HC of a major team.
Unlike the coaches that failed before him, I actually think that if he does some soul searching makes real, substantial, internal changes, he still has a chance to be a CFB HC, but only if he "fires" the current Manny and replaces him with one that has fixed these things.
Good luck, Manny. I know you tried and if it means anything, I was rooting for you to prove me wrong this season and wished you had.