“You Ain’t Seen Nothing Yet” was first recorded by Randy Bachman and Bachman Turner Overdrive to make fun of his brother Gary who had a speech problem at the the time.
During the microphone checks Randy wanted to record a stuttering version to give to Gary, but the record company liked it better than the non-stuttering version, and released it.
In addition, the band recorded it as a scratch track just to get the recording levels right, but was released while they were on tour.
It was later re-mastered to correct the out-of-tune insturments.
By the way, You Ain’t Seen Nothing Yet is a double-negative — and grammatically incorrect.
Take a look at this promo clip: