New York Giants B.P. (Before Parcells): One playoff appearance in 10 years.
New York Giants U.P. (Under Parcells): 3-12-1 his first year, back-to-back playoff appearances in years 2 and 3, Super Bowl Trophy in year four and one more to follow.
New England Patriots B.P.: 2-14 in 1992, under .500 for four straight years including a 1-15 campaign in 1990 (when he was going to the Super Bowl with the Giants).
New England Patriots U.P.: 5-11 in his first year, 10-6 and in playoffs in second. Super Bowl appearance in 1996.
New York Jets B.P.: Four wins in two years, including 1-15 in 1996 (when he was going to the SB with the Pats).
New York Jets U.P.: 9-7 in first year, 12-4 in second season with appearance in AFC Championship.
Dallas Cowboys B.P.: Three consecutive 5-11 seasons.
Dallas Cowboys U.P.: 10-6 in first year with a playoff appearance, consecutive 9-7 seasons in 2005 and 2006 with one playoff appearance (no playoff wins). He had three seasons above .500 with Quincy Carter, Drew Bledsoe and Tony Romo at quarterback.
Sorry, but the man is one helluva coach. He took every franchise he ever coached from total **** to the playoffs in two years or less.