I always love it when people characterize any given COA as maaaaagic. As though the generic paper with a random sports card store name (that may or may not have ever existed and probably isn't in business anymore if it did) on it seals the deal.
Yup. First thing my friends ask when they see my collection is "And you have paperwork and certificates for all of these right?". I then go on to tell them that I study these, and KNOW they are 100% authentic, and I doubt they believe me.
Fact is, 90% of "autograph collectors" will buy a forgery with a "COA" over an uncerted authentic. MORONS.