Kincaid is a native of Alabama and was the star quarterback at Virginia Tech. He was the starter for the 1967 and 1968 seasons, and in 1968, he took the team to a 7-4 record, including a Liberty Bowl appearance against Mississippi. However, he lost the starting job in the second game of the 1969 season, after playing well in the season opener against Alabama. His career record was 122 completions in 261 attempts for 1,202 yards and five touchdowns. He was intercepted 13 times. He also rushed for 499 yards and two touchdowns.
Kincaid became offensive coordinator at Wyoming under Pat Dye, and succeeded him as head coach after the 1980 season. He signed a three-year contract at $45,000 per year, agreeing to have 20% of the salary withheld in interest-bearing escrow and forfeited if he broke his contract. In 1983, he was courted by Memphis State University after head coach Rex Dockery died in a plane crash, but he withdrew his name from consideration, deciding to remain at Wyoming.
In his five years leading Wyoming, he compiled a record of 29–29. Following a 3–8 season in 1985, he was fired and was succeeded by Dennis Erickson.
Kincaid worked as a sports consultant in Decatur, Alabama, and then returned to Tuscaloosa and coaching, again serving as an assistant at the University of Alabama. From there, he went on to become head coach at Arkansas State.
In 1992, his 23-year marriage ended in divorce. His ex-wife, Nanci Kincaid, married Arizona head coach Dick Tomey in 1997. However, the couple remained close, and as a writer in North Carolina, she still was assisting him in player recruiting in 1998 when he was an assistant head football coach and offensive coordinator at Temple University.