There's a difference, though. Gus was at Arkansas for a year as OC in 2006. He then went to Tulsa for two years. Chizik hired him at Auburn as OC, and he stayed for three years. He then got a year as HC at Arky State before going back to Auburn. He had six years of experience via being an assistant coach before taking the Arkansas State job. He was fortunate to get his first college gig as a SEC OC.All I know is that if I were an AD looking for a head coach next year (a list that should have half the big 10 schools) this dude already has my attention. In fact, depending on how the season plays out for UAB and Vandy/Arky, there may be a couple of SEC schools willing to take a risk on Clark. He's not exactly an unknown commodity given his tenure at Prattville and we know for a fact that long time high school coaches can have success at the next level as did Gus.
Clark, OTOH, left Prattville in the spring of 2008 to be DC at a start-up program. They recruited and prepared the program for a year and had their first season in 2009. Their opponents were teams like Hargrave and JUCOs. That was what Clark faced in 2009 and 2010. In 2011 and 2012, he faced some Power 5 schools but was in FCS and the Sun Belt. He has a year of head coaching experience at FCS Jacksonville State.
Gus was able to start his collegiate coaching career in the SEC. Clark started at a start-up South Alabama program.
Gus was an assistant for six years. Clark was an assistant with on the field experience for five years.
Clark will get his chance in a few years if he continues to do well, but he will have to go 11-1 and another solid season next year in order to get to a major coaching job within the next two to three years.