Butter vs. Margarine - Which is Better?

I found this to be helpful as well! There is a lot of research supporting this. So, you could find this information in many different resources. 

http://lowfatcooking.about.com/od/faqs/f/buttermargarine.htm

I noticed towards the end of the article it said you can often get away with using half the amount of butter called for in cookie recipes. 

I'm wondering if substituting some apple sauce is how you do it. I rarely do that, because I just try to avoid making cookies. My self resolve is terrible when there are home baked treats in the home! 

Margaret