L-S or S-L?

can someone please tell me in detail what each one is. thanks.

Go to the site store and get a copy of CFTS and you’ll get the whole picture. Also the Vanc 04 download has examples of the approach each one takes. remember that they diverge in approach the most at the beginning of the year and move towards each other as the year progresses

That comment has made me question my understanding of the different approaches slightly!