I don't hold with a "bluffing stage". Neither of mine have had one, so they obviously don't subscribe to it either!
I've written to a few of the most respected bird trainers that i know of and none of them have given any support whatsoever to the idea of a "bluffing stage". Barbara Heidenreich has written a blog about it too
Barbara's Force Free Animal Training Talk: Do Animals Bluff?
Another was surprised to hear of the idea as she has raised Alexandrines (a closely related species) and had not seen any symptoms of "bluffing" in her birds. A prominent proponent of Applied Behaviour Analysis, who also keeps an alex, regards the "bluffing" theory as the result of old fashioned, dominance based handling techniques. Another behaviourist puts it down to the old fashioned techniques combined with the new parrot owners inexperience in reading and responding appropriately to the body language of their new pet.... All of them strongly disagreed with the advice in the "article" about "bluffing" that I had sent them (you can find it on an interenet search) and did not subscribe to the idea of a"bluffing stage".
Indian ringnecks are quite sensitive birds, they don't seem to be as tolerant of things they feel uncomfortable with as some species may be. When they are uncomfortable with styles of handling, they may show aggression, especially if they are not given a choice on whether they would like to participate or not. If we step back and ask them whether or not they would like to engage, in my experience, they are usually up for anything as long as they haven't been coerced into it.
Btw if you look on YouTube for "bluffing indian ringneck" and assess what the person in a video is doing, and what the bird is displaying in regards to comfort-level and body language in the interaction, it kind of justifies the bird to bite them.
The other thing that I believe contributes to the "bluffing" is the comparative reaction time between an indian ringneck and us. I watch them interact with each other and they can have a whole disbute over a toy or something in the time it take us to lift a hand. They will have gone through the "warning signs" (pinning eyes, lifted feathers, maybe even an opened beak) in a second and someone will have backed down in that time. They are also subtle, which makes it a bit hard to read them sometimes.
My boyfriend and I are both are convinced that our birds have learned to draw out the warning signals to suit our slow reflexes...They give us much longer warnings than we observe between them and their birdy friends. We both believe that our birds don't actually like to bite, it is their last resort.
We put forward the theory that it can take some time for a young ringneck to learn that humans take longer to respond to ringneck body language than the ringneck expects. In some cases, where the human does not respond to any ringneck signals, it turns into a prolonged period of biting because the ringneck is trying to state his/her case and the human is very stubborn. Possibly the human is the one "bluffing"...
Beyond that, I'll just say that indian ringnecks can be loud, most don't like pats and cuddles yet still require tons of attention and stimulation. They are bright and quick and beautiful.
Maybe your gcc would like a same-species friend?
I don't know what to do
