McCoy said he was "a bit stubborn" after Tebow was made the starter in 2011, but then realized he needed to change the offense.
"You take advantage of what your players do best," McCoy said.
With the Chargers, McCoy will work with Philip Rivers, who struggled this season in large part because he was under siege behind a shaky offensive line. Rivers was sacked 49 times and committed 22 turnovers, giving him 47 turnovers in two seasons.
"You go through the disappointment from the season and losing your coach to now having a new GM, new coach, and you get excited and ready to go for this 2013 season," Rivers said.
"Once I found out that we were bringing him in on Monday, I was hoping he wasn't going to leave again. I'm excited that was the case and I'm looking forward to getting started."
Denver swept the Chargers in 2012, including an epic 35-24 victory at San Diego on Oct. 15 when Manning calmly led the Broncos back from a 24-0 halftime deficit.
McCoy was a walk-on quarterback at Long Beach State under coach George Allen. After the 49ers dropped football, he transferred to Utah. He signed with the Broncos as a free agent and spent his rookie season on Green Bay's practice squad. He had stops in NFL Europe and with San Francisco, Philadelphia and in the CFL. He began his pro coaching career with Carolina before moving to the Broncos in 2009.
McCoy said he learned about detail and preparation from Allen, who coached the Los Angeles Rams and Washington Redskins.
"He was not a big yeller and screamer, he just expected you to go out there and do your job and execute the system the way it was supposed to be executed," McCoy said.
McCoy said he planned to hire an offensive coordinator to call plays. Turner called his own plays. McCoy was non-committal about defensive coordinator John Pagano, saying he planned to evaluate the entire staff.
AP Sports Writers John Wawrow in Buffalo and Arnie Stapleton in Denver contributed to this report.
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