is it possible he just wanted more money and using lack of a president as an excuse to leave without looking like 'the bad guy'?
maybe he doesn't see the football team doing good in the new look big ten and just decided this was his chance to make another move.
it's just a theory but it makes sense. pederson/eichrost/moos all lasted 5 years and trev is in year 4, so maybe he didn't want to be the next fall guy and ruin his legacy here.
bottom line is money talks, and A&M has a lot of it. and its worth noting he'll save 7% per year in state income taxes in texas.