I don't agree with grabbing their beaks for any reason...... It isn't a behaviour that they can possibly understand. They are not dogs or kids. They should not to be expected to behave as such.
Our birds need to be treated as the species they are, They should NOT be expected to behave as a family member with the same expectations we expect from our dogs and kids, etc. they have special needs and need to be treated in the language that they understand, not ours.
No offense Nancy, I'm not trying to pick a fight or arguement, but you always tell us how Sophie must live by YOUR rules, YOU are the PARENT. That is not at all how I believe a relationship should be with any bird. I can't help but wonder if Sophie is so well behaved as you say, because she is fearful and not allowed to flourish as a true grey.......JMHO