What keeps you dominant is dominant talent. Dominant talent generally leaves early. Teams that are consistently dominant will consistently lose talent early. But they stay dominant by recruiting more dominant talent. If you're not losing talent early as a matter of routine, you are probably not dominant. So, to answer the question - yes, as long as LSU keeps recruiting dominant talent.
That is an interesting theory, but I don't see how it applies well to last year's squad. Was last year's team dominant? I will venture to say that the defense was dominant at times, but a defense rarely makes a whole team. How about Special Teams? Offense is a definite no. Some of the talent you lost underperformed last season. Based on 2012's results alone, LSU did not lost much dominant talent.
It's difficult to call any program in the SEC dominant nowadays. Alabama has done a good job of dominating the West Division teams not named LSU. I'll call LSU even with Alabama, but other than that would you call LSU dominant within the division? How about the conference? The SEC has too many good teams now, and those 1-hit wonders (2010 Auburn, 2012 Texas A&M) for any program to truly be on top. No one's truly dominant. Alabama's program is as close as it gets.