I wrote a long post that disappeared into cyber space somehow..(grin) but I have to respectfully disagree on the greys biting issue. I think that of all species of birds, they tend to bite less.
Both of my greys seldom bite at all. Kiri is 20 years old and Phinney is 16. For three years, I took Phinney to the assisted living area of a nursing home once or twice a week and we did tricks for the oldsters. I couldn't do that if I did not absolutely trust her. I trust Phinney 100%. The only time she ever bites is if we are playing...rough play...and it's more like a puppy bites. She goes for an object and misses. She does not fear bite ever. Kiri does not fear bite. If a grey bites, it is usually a manipulation. Often, it is a manipulation they are taught. Greys are usually easy because if you talk to them and tell them what you are going to do before you do it, they can learn to go along with it. I can't talk my Senegals into much at all. They are more stubborn than the greys.
I think the biting and attacking stuff is way, way over the top in these discussions. Yes, parrots bite. Probably...most parrots will bite at one time or another but you just recognize their boundaries and work with that. I don't let strangers pet Phinney because she doesn't like it...instead, she waves. It works out really well. One of my Senegals, Bailey...goes to just about anybody and really doesn't bite very often. He really loves my husband and my husband is an absolute WOOS about biting. He wouldn't put up with that at all. I also think attacking is about managing what the animal perceives as a "scarce resource". Senegals (not greys) can be emotional about what they perceive as a "Scarce resource".