Went to open a bank account for The Brat this week and the bank does not accept small birth certificates as proof of ID . Had to trudge all the way home and find her full one 
RBS accepted one ~ maybe the fact that I have other accounts with them helped

Tell me were they stoopid enough to ask to see a utility bill in her name to prove her residence?
Wife had probs with that .... all bills are in my name.
Birth Cert tells them sod all accept her age and the fact she is British born. Proves little else and that can be done with the short version.
My verdict ~ Poor staff training!
But if questioned I'm happy to bet they would trot out a lot of bulls hit about identity theft.
I have the full birth certs of many of my ancestors .. they cost £7 each to get from the National Records Office ..... I could take any one of them in as proof of identity.