"If ifs and buts were candy and nuts, we’d all have a merry Christmas” was a proverb of Don Meredith, former SMU and Dallas Cowboys quarterback and Monday Night Football announcer. The proverb (in other forms) is older, but Meredith helped popularize it.


Wikipedia: Don Meredith
Joseph Don (Dandy Don) Meredith (born April 10, 1938 in Mount Vernon, Texas) was an American football quarterback for the Dallas Cowboys, football commentator, and entertainer.
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Post-football career
Following his football career, Meredith became a color commentator for ABC’s Monday Night Football beginning in 1970. He left for three seasons (1974 to 1976) to work with Curt Gowdy at NBC, then returned to MNF partners Frank Gifford and Howard Cosell. His approach to color commentary was light-hearted and folksy, in contrast to Cosell’s detailed and intellectual analysis and Gifford’s rather pondorous play-by-play technique. He was known for singing “Turn out the lights, the party’s over” at the time the game was apparently decided.

17 December 1970, Ada (OK) Evening News, pg. 7, col. 1:
Howard: “If Los Angeles wins, it’s a big one, but San Francisco is still very much in it.”
Dan: “If ifs and buts were candy and nuts, we’d all have a merry Christmas.”
Howard: “I didn’t think you’d remember that old canard.”
Dan: “Is that what it was?”

18 March 1971, Chicago , pg. C3:
IF IFS AND NUTS were candy and nuts, someone said, Wisconsin would be the N.
C. A. A. track champion.

2 April 1971, Chicago Tribune, pg. C3:
“There’s an old saying, Ernie. It goes something like this: ‘If all the ifs and buts were candy and nuts, what a wonderful Christmas it would be.’”

26 November 1972, Washington Post, pg. C6:
On-the-air and at public meetings, Meredith is the bucolic, puppy-friendly, old-shoe, ex-athlete.  He has made a running gag, lasting for three seasons, about his inability to explain pass interference.  He is filled with country boy wisdom:
“If ifs and buts were candy and nuts,
We’d all have a Merry Christmas.”

10 March 1974, Washington Post, pg. C10:
“If ‘ifs’ and ‘buts’ were candy and nuts we’d all have a merry Christmas,” Meredith said, repeating an on-the-air favorite.