Balance in all things is so important. And there are many different types of parrots from all around the world, and it stands to reason that their dietary needs may be even more species specific than we realizse. Some parrots may require little to no protein, and others may be truly omnivores..

Correct. Tailoring the diet to the species is the ideal but the problem is that we simply do not know what the dietary requirements of parrots are. We have a vague idea with tiels and budgies but not the larger parrots. You will see parrot food manufacturers making claims on their products to the effect of "complete nutrition", "the closest to their natural diet", "under the supervision of avian nutritionists" and stuff like that, but this is all marketing bullcrap. We don't even know how much protein they are supposed to eat! If you look at the labels, you will see that they all guarantee a minimum (usually around 14 or 15 %) but they don't actually give you an ACTUAL protein content... for all you know, it could be 25%!

And yes, you are absolutely right, protein is necessary. I've never come across a bird that had a protein deficiency, though... but I've seen six year old grays with cyrrhosis and macaws with xanthomas and zons with fatty tumors from too much protein and fat in their diet. There was one diagnosed with it in this or another forum, a tiel if I remember correctly, and the diagnosis was made based on the dull plumage and cracking/peeling beak. But once the bird started getting more beta-carotene the symptoms disappeared so it was obviously not a lack of protein but one of vitamin A that was causing it.

The problem I have with 'moderation' is that it's the kind of word that can mean anything. It's very subjective and can be stretched either way, if you know what I mean. What is moderation? A quarter size piece of skinless chicken breast from an organically raised, free-pastured, lean chicken once a year as a special treat or a fatty Perdue roaster's leg once a week? I would have no problem with the first for a bird that's healthy, young, always eats a good, organic, varied diet with plenty of veggies and fruits and gets lots of exercise. I would even have no problem with this bird getting it once a month! But when you are talking about captive birds, you are usually talking about birds that are been free-fed seeds and/or pellets all day long, that get bread as a treat on a regular basis, that stay in their cages most of the time and hardly fly at all, that eat regular food instead of organic, that share their humans dinner almost daily.... and that's a different story altogether. That's a borderline bird. And most captive birds are borderline.

I think that, when it comes to parrots diets (and everything else, for that matter), one should constantly strive for perfection and giving a herbivore meat does not fall under that heading in my book.