LSU had one bad season prior to Chavis' arrival, the year before that the Geauxmers had the top ranked defense in the SEC.
Louisiana produces more NFL talent per-capita than any other state by a long, long ways, and they're the ONLY program in the country that has a talent-rich state entirely to themselves.
Chavis is an adequate coach who doesn't do much legwork in the recruiting game who happens to be at the best DC gig in the game.
And for the record, I couldn't care less about what other coaches have to say about him. With rare exception, coaches won't ever publicly say anything negative about their peers, and anybody using it to bolster their argument about somebody is a massive idiot.