@margo,
Margo my cats had always been very nice to me in that they have never used their claws on me. Not a statement that I can say cover their vets however.
I had one little girl I could do anything to up to even giving her shots myself but she was a terror in the vet office.
Once they had her on the table and I was holding her as she was trying her little heart out to claw them aroud me. The stupid vet said I should leave as my being there was just granting her permisson to act out!
The long and short of the story is after I let her with them I never hear such cries of pains coming out of the room and they was not cries of pain from my cat either.
It look like they had been dealing with a wild cat instead of my little tiny girl and I am sure they up my bill when I could not keep from laughing. She needed my permission indeed!