Ok here goes benifits of degreeing cams?

Had a neighbor build a Pontiac engine for a street car many years ago. Ran ok , but he knew it should run better. Went thru everything, and then checked the cam centerline. Found the cam was 10 degrees retarded. Figured someone cut the slot for the cam key wrong. So I centerline everything I build now.
Ok so I bought the kit per Rusty Rat Rod's suggestion. As he is more knowledgeable in this than me and im wanting to learn. . received it today. So I will be freezing my coconuts off as it just snowed and is 18*out. But im gonna try it out.