Just because it isn't conventional does't mean its a gimmick. Uninformed fans have been calling this offense a gimmick for the last 4 years. You don't win the number of games at the division 1 level this offense has, by a few little trick plays or by luck.
Professional defensive coordinators have been stressing out how to stop this play style for the last 4+ years with limited success. Chip's gimmicks have been adopted by college teams across the nation, and are being studied and applied at the NFL level. This is a long term trend, not some recent flash in the pan. High school and college players who are growing up running this offense today... will be accustomed to and perfecting this offense in the NFL tomorrow.
Just listen to Gruden, Jaws, Dilfer, and many others who call this the future of the NFL. They know a bit more about football concepts than those who easily dismiss this play style as a just a fad.