He was in Miami for the 2000 and 2001 seasons, they went 11-5 both years with Jay Fiedler at QB. They didn't return to the playoffs until 2008. I'm not sure what you're refering to.
Also, this from the Bills website:
"Gailey’s resume speaks for itself, he has spent nine of his previous 15 NFL seasons as either a head coach or offensive coordinator. During those nine seasons, his teams have made the playoffs seven times and boasted a 1,000-yard rusher on seven different occasions. In total, he has made playoff appearances in 11 of his 15 seasons in NFL coaching. His resume also boasts four Super Bowl berths, including one with Pittsburgh (XXX) and three with Denver (XXI, XXII and XXIV)."
http://www.buffalobills.com/team/coaches/chan-gailey/dadb1683-1a19-4811-83c0-b9347f2240ba