I can tune a guitar without a fork or any other aid. Don't know it that really counts though, because I suppose it's only perfect pitch in that particular setting.
Play a note for me at random, in some other setting, and I MIGHT be able to tell you what it is, but probably not.
Can I tell when a note is "off?" Yes. Always. to an annoying degree according to everyone around me.
I honestly can't understand those who can't tell.
It's as obvious to me as something on a balance scale being off balance. But then again, most people I know can't tell that as easily as I can either.
The problem with me though, is that though my ears might be near "perfect pitch," my fingers aren't.
What I mean is that I've heard that musicians with "true" perfect pitch can listen to a melody, or chord progression, or both, once, then play it back to perfection.
I can't do that, because though I know what I heard, I can't make my brain communicate that way to my hands and fingers. My appendages do whatever the heck they want to!
As a result, most of the music I write, I write with visual patterns, instead of sonic ones. For example, when I look at my guitar neck, I know that if I move my hands in certain patterns, with certain fingerings, I can construct some good harmonies and melodies based on the visual patterns I imagine.
I now use Sibelius to write a lot of my music, and the same applies with it. I "see" the music without hearing it, and know what will work and what won't. Of course, it does help that I can hear it at the same time, while writing it. But I don't even think about what the notes are while I'm dropping them in there.
To me, it's irrelevant. Ask me what key any song is in that I've written, and you'll get a blank look, followed by, "It goes like this," then I'll play it.
Reminds me of Nigel from Spinal Tap, and the amps that "go to eleven."
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I'm not likely to be around much longer. As before when I first signed up here years ago, I'm finding that after a long hiatus, and after only a few days back on here, I'm spending way too much time here again already. So I'm requesting my account be locked, banned or whatever. It's just time. Until then, well, I dunno...