The problem is that you talk about what you perceive as flaws in the disease model (theory) in your original post, and unsubstantiatedly claim that 'It posits one notion of normal and then divides everything into "normal therefore fine" or "different, therefore broken".', which is incorrect (as pointed out by DanBC).
If someone applies the model incorrectly, that doesn't undermine the model.
I have looked, and I have heard the arguments you are talking about, some of which I agree with (as you can see from earlier posts), but a common sentiment amongst some of these seem to be the almost conspiratorial belief that it is all based upon suppressing anything other than normal behavior.
I think it is more reasonable to suggest that the bar might be set too low when it comes to this diagnosis in the U.S., than it is to discredit the illness entirely because of what amounts to misdiagnosis. The subject is fraught with nuance.
As for the use of sources, there is clearly a discrepancy between our posts, though mine are admittedly often from Wikipedia.
If you would like a better source, take a look at Hallowell's work. His basic take is that ADHD is not a disease, but a trait:
http://www.drhallowell.com/add-adhd/
Of course, he's only a psychiatrist who specializes in ADHD and has written a half-dozen books on the topic, so I'm sure he's just lacking your subtle understanding of the perfection of the disease model. And probably a conspiracy theorist too; there are so many of those on the Harvard Medical School faculty.
And if you'd like more on how the disease model is misused, start with the literature on the medicalization of deviance:
https://scholar.google.com/scholar?q=medicalization+of+devia...
What you're talking about in this thread doesn't translate to applying the model "without nuance", but to wrongly apply the model or to not apply the model at all (since the model is not followed).
That's why I think your first post is wrong; the disease model does not claim that deviancy == illness. Rather, it claims that the identified problematic behavior is a result of a chemical/biological issue, and doesn't deal with definition of problems at all.
Also worth noting is that the purely biologic view isn't really en vogue any more. AFAIK, the biopsychosocial model is more popular.
In practice, it is valuable to view mental disorders as (i.e. not claim that they are) illnesses, one of the reasons for which you touch upon in your original post.
I have of course heard arguments like Hallowell's before, and I don't think that they're entirely unreasonable, although the gist of them can be applied to psychiatric diagnoses in general, seeing that all symptoms and traits can be said to exist on a scale/spectrum/continuum. Most literature I've seen readily acknowledges this (and notes pitfalls of other kinds, like being somewhat based on social norms). This is the one of the nuances I've previously alluded to.
As I think is quite clear from our exchange, positions like these are not the ones i disagree with, nor the ones I refer to as conspiratorial – that would be those that actually posit conspiratorial "theories", e.g. willful persecution of those outside the "normal" by practitioners, the powers that be, etc.
I'll refrain from commenting on your rude sarcasm and unreasonable assumptions, but know that cherry picking a source and appealing to its authority doesn't make for a convincing (nor logical) argument.
I'm also familiar with medicalization of deviance, though I don't see how this pertains to the disease model, as this kind of social control is possible (and has been performed) via a plethora of means.
P.S. Just came across an editorial [0] that deals with some of this that might be of interest.
And I certainly don't go attacking straw men before you've even had a chance to answer accusations (as in the rude sarcasm part).
I also note that you have yet to back up your original assertion that the disease model "posits one notion of normal and then divides everything into "normal therefore fine" or "different, therefore broken"', which is hardly surprising, as it doesn't deal with this definition at all.
Take care.
As to, "I have yet to see any reasonable argument" bit, I can certainly believe it. But I think that's mainly because you haven't looked. Plenty of people have talked about rampant overdiagnosis of ADHD in the US because putting everybody on stimulants makes classrooms easier to control. Overdiagnosis here means taking healthy but inconvenient behavior and pathologizing it. If people only have "dysfunction" in particular classroom environments with particular teachers, I think it's reasonable to suggest that what's dysfunctional is the environment and the expectation of universal conformity, not the people who are different.
It seems like we are mainly talking in circles here, and given that this is a topic on which I have paid attention to for a couple of decades and also have direct experience, your arguments from Wikipedia theory links aren't going to do much for me. Maybe we should stop now?