as far as i know, coil split is when using one coil in a humbucker. and coil tap is when using a switch or a potentiometer to reduce the amount of winding in the pickup you use, making it hotter, or less hot manually on the fly.
You know...youre alright man! I like how you are a consistently cool poster...and rational too! So whats the story with your avatar? And Free Fenson!!!