While Marc Trestman’s success in the Canadian Football League may help him succeed with the Chicago Bears, not every head coach can win in both American and Canadian pro football. Here are five head coaches who should’ve just stayed in one country:Jerry Williams - A longtime assistant with the Philadelphia Eagles and the father of the nickel defense, Williams had success with the Calgary Stampeders before new Eagles owner Leonard Tose hired Jerry in 1969. As indicative of the Eagles of that era, he went 7-22-2 in two seasons, but then went to Hamilton, where he led the Tiger-Cats to a Grey Cup win in 1972.Hugh Campbell - Sometimes a coach was only meant to be successful with one team. In Hugh Campbell’s case, winning ten championships in the CFL as a player, coach and executive more than make up for his lack of success in America. In six seasons coaching the Edmonton Eskimos in the late 1970’s and early 1980’s, Campbell made six consecutive Grey Cup finals, winning five in a row with Warren Moon sharing QB duties with Tom Wilkinson. Campbell couldn’t repeat his success with guys such as Mike Rae and Tom Ramsey while coaching the USFL’s Los Angeles Express in 1983, nor could he repeat his success with Moon in the NFL, leading the Oilers to consecutive losing seasons in 1984 and 1985. Campbell went on to spend two more decades with Edmonton as their general manager and later President.Ron Meyer - The CFL’s brief expansion into America actually fielded some good teams; Ron Meyer’s Las Vegas Posse was not one of them. The Posse were a spectacular failure on almost every level, going 5-13 in 1994 and barely avoided folding near the end of their sole season. Meyer was always a hit-or-miss coach in college and the pros, leading the Patriots and Colts to playoff berths and bringing SMU to national prominence, while never succeeding in the postseason. Meyer didn’t have enough time to offset his failures in Las Vegas, but went on to coach in the XFL, leading the Chicago Enforcers to a 5-5 record in their only season.Kay Stephenson - Although never a true success in the Canadian Football League, Kay Stephenson certainly improved on his NFL record. As the head coach of the Buffalo Bills from 1983 through part of 1985, Stephenson went 10-26, and according to his Wikipedia entry, was not even sure why owner Ralph Wilson hired him in the first place. Stephenson’s CFL career began when his WLAF champion Sacramento Surge transferred after the World League’s hiatus in 1993. Although what became the Gold Miners were not successful in Sacramento, they went 12-6 in their final season in 1995, as the San Antonio Texans.Mike Riley - After winning the 1988 and 1990 Grey Cups with the Winnipeg Blue Bombers, the then 37-year old Riley moved to the World League of American Football, where coaching the San Antonio Riders should have been a stepping stone to a successful NFL career. However, Mike Riley might have been the victim of bad timing with his only NFL head coaching gig. When Riley took the reins in San Diego in 1999, Ryan Leaf was the Chargers’ quarterback. The Chargers won only fourteen games in three seasons under Riley, with eight of them coming in his first season. San Diego would not have been bad enough to get LaDainian Tomlinson and Drew Brees in the same draft had they not finished 1-15 in 2000, but Riley only lasted a single season after that, and has spent the last decade having relative success at Oregon State..