Hi..
I agree with many of the responses here so far, at least partially. I wish I could respond to them all, but they're popping up so fast it's tough, lol.
True, loudspeakers are all "flawed" as well, but not like THIS. I do agree that headphones can still be very enjoyable at times, and often more "intimate" than any loudspeaker. And yes, it's really about enjoyment, not how true something seems to be to a recording. However, they're all so different with pronounced flaws that I often find it difficult to enjoy them. For instance, right now.. the pronounced top end on these HD600's are giving the highs a sense of poking me in the eye. It's a very similar feeling to that of a poorly implemented tweeter.
Yes, everything adds its own color, loudspeakers certainly included. But like I said, it's just not as bad as any headphone I've ever tried. It's like this.. with speakers, the room and distance are a problem. With headphones, it's the headphones themselves, and the way they interact with your ears (and of course, each person's ears are different). As far as any sense of accuracy goes, it's not that difficult to do with near field monitors. Even a single 4" driver in the near field can work well (along with something else to help with the low frequencies).
And no, I don't have OCD, lol. Funny you say that though, as I know a couple people who do. Horrible condition to have to deal with! I can understand your reasons for saying that though, as OCD often makes everything so difficult. It's really not like that for me though. I just want a decently accurate set of headphones that are easier for me to enjoy, without highs poking me in the face and worsening my tinnitus, mids shouting at me, or over-emphasized midbass. That's all. But with headphones, it seems impossible.