Finding the key from the last chord assumes you have the song in some sort of format which allows you to play it multiple times.

On the radio..... the goal is to figure it out fast and jump in the deep end and swim.


You can find my music at:
www.herbhartley.com
Add nothing that adds nothing to the music.
You can make excuses or you can make progress but not both.

The magic you are looking for is in the work you are avoiding.