In most songs the ad-libs and chord substitutions come during the last chorus…because they’re built on the foundation of the audience knowing the regular chorus, which by the last chorus, we’ve heard two or three times.
But Christmas songs are different…because most Christmas songs are covers of beloved classics.
The ‘way the song goes’ is already embedded deep in our brains.
So the ad-libs and chord substitutions can start right from the beginning and we love it. We can appreciate the changes because we know what they’ve been changed from.
When making your next thing…it’s important to recognize to what degree the standard is set and what you’re going to do with it.