I believe you, but it didn't work for my son. Below is a copy and paste from travel.state.gov. Believe me, I tried to argue with them, told them something similar to what you wrote about the validity, but they required the long form. I found a site that got me the long form in something like 2 days, so it worked out ok but they definitely required the long form. I don't know, maybe they changed their policy in the past 3 months -- this was this past October.
"*A certified birth certificate has a registrar's raised, embossed, impressed or multicolored seal, registrar's signature, and the date the certificate was filed with the registrar's office, which must be within 1 year of your birth. Please note, some short (abstract) versions of birth certificates may not be acceptable for passport purposes."
leonardo wrote: