From an outsider - I think that the LSU culture of winning under Miles was well established. You ran into an Alabama team that was just a hair better and the powers behind the curtain let that get into their heads. Everything became about beating Alabama. When you become results oriented, the process that produces those good results falls apart.
LSU needs to find a head coach who does things the right way, with every game treated equally and success being measured by quality preparation and play, not the scoreboard.
Mostly agree with this, and with most of what's been posted above this. Saban has been inside Les' head from the moment he was hired at UA - and he's still inside many heads in Baton Rouge. Les Very Nearly blew the 2007 game against us (a game that "Should" have been an LSu ROUT) by trying to embarrass Saban rather than simply trying to win the game.
AND - da Tiga's surely have suffered from QB play. Sure, they've had some lean years at QB, but honestly, it's not like its been THAT bad, THAT often. They've had several QB's who were at least "Serviceable" since 2005.
And again - honestly, how many "Great" QB's has Alabama had under Nick Saban? AJ is the only one (so far) who's seriously threatened to be an NFL starter - and even AJ isn't a "Lock" unless it happens for him this fall - his 5th year in the NFL??
I think the underlying problem is a cultural one. I lived in LA for several years before I was blessed to be able to move to "God's Country", Lower Alabama, and I can tell you (even though stereotypes are always unfair) - Louisiana, due in part to its ethnic composition, has more than its share of "Big talkers"; Front-runners and blow-hards who want to talk trash, but can't always back it up when challenged. (For example, the Weed Weasel back in 2011).
This IMO likely contributes a lot to their problem with early departures. To be sure, we are NOT Immune from the problem, and we've seen guys leave before they really should have. But we seem to control it better than most in our position.
At LSu, you have tons of "Big Talkers" with RAGING EGO's - (at some level) they seem to think they just have to show up and the NFL money will flow like water. I suspect, since they seem to arrive at LSU with this attitude, many of them probably don't have much choice BUT to leave, as they probably have invested VERY LITTLE EFFORT into getting an actual education, beyond the minimum necessary to stay eligible. Probably more than a few that have "progress toward degree" (or whatever the proper term is) issues.