Well my sweet Tia has been terrorizing me now every few days for about three years (she is nearly 5) and I thought I tried everything. I tried ignoring the behaviour and respecting her boundaries and it didn't stop. I tried wobbling, and distraction. Finally I thought the next time she does it I am going to put my hand over her back and gently and firmly cup her and give her kisses (you have to watch because she tries to bite while you try to cup her. I theorized that she was in a power struggle with me and she needed to know I was in charge.Wow after just one time I noticed a difference. Up until now, I don't usually touch Tia anywhere much except give her kisses on the beak because she loves my other bird Carlos and she doesn't like being touched. She is a good step upper though. Otherwise though she is a great bird and would do sweet sounds back and forth with me and talk to me and give me kisses.
I cupped and kissed her about 8 times in the past week but each time I had to do it was for a lighter nip as opposed to the welts she would inflict just a week ago. I am so happy and she seems happier too. I think she is more comfortable knowing that she doesn't have to be in a power struggle with me. She can feel safe and secure with me as the head of the flock (like being safe with a parent when you are a child) (although I read there is no true head of the flock it seems to be working very well). Now we are both relaxed when she plays in my hair and she even is more comfortable out of her cage for longer times.
I just wanted to share this with everyone who was having this problem - I am amazed at the change so quickly. I am sure I will have to keep it up when she challenges me but now I almost look forward to getting to hold her cute little body and give those sweet wings some kisses.
Also so long as I stay on top of it there won't be any more welts!Hugs, Mara
These babies of ours certainly do have their own personality....Glad you finally figured Tia out Mara.... 
And we always will love them....