I have ADHD to thank for my self-education and following career, where by I cannot resist spending hours on things that are highly stimulating, such as the next interesting thing to learn in computing, which is pretty much infinite.
The tragedy is that once something is learned or done so many times it becomes routine and boring. It doesn't provide the same mental stimulation. Unfortunately, in most businesses, the types of problems are almost always in the routine category. This I've found is where my attention faulters.
I'm not saying you are one but ADHD deniers tend to dismiss symptoms described in isolation off as "oh this is normal". Without the ability to describe in coherent way how deep the rabbit hole actually goes, many people with ADHD suffer needlessly when trying to seek help.
ADHD symptoms are often described as "everybody experiences the symptoms to at least some small degree, perhaps in combination or maybe one alone, but a sufferer is where they experience the majority of the symptoms to a massive degree on a daily basis". In a lot of ways, it DOES look normal. What isn't normal is how extensive the symptoms are and how much of impact they have on daily functioning.
I can only imagine that its frustrating to hear such comments over and over again from people who have no idea about your situation. However the problem is that partially this is the problem of rampant ADHD miss-diagnoses which creates natural tendency to first question it.
While it won't make you an expert, it will perhaps help you understand what it is people with ADHD suffer through.
There are bad doctors and bad policies out there which are being resolved. They don't diagnose young children anymore even if it seems likely since some children will "catch up" and stop exhibiting symptoms. This is the source of many teens and adults today that discover that once they stop taking medication they don't need it. As our understanding of the disorder grows so does our ability to accurately diagnose it.
That said, while I can't speak for the person you replied to that shit is incredibly frustrating. Your empathy is unusual and appreciated but regardless of the rate of misdiagnosis you are not a doctor and are admittedly entirely ignorant about it.
I can't emphasize enough to those reading this that no matter how much you might doubt it, the people who work in this field do in fact know more about it than you do and making an armchair diagnosis or questioning a doctor's diagnosis does nothing but make you look like the kind of know-it-all that really knows nothing while maligning someone who has to read ignorant comments like yours in every damn discussion on the internet where ADHD comes up.
I know it's easy to think you've got all of the answers when understanding complex problems comes naturally but these doctors don't spend nearly a decade or more in school sitting around with their thumbs up their asses. There are tremendous amounts of research going into ADHD by doctors and scientists who actually understand the problem domain more thoroughly than you ever could simply by reading a headline about a study that documents the rate of misdiagnosis for a disorder.
Please understand this disorder is not some cry for attention or an exaggeration of one or two symptoms you mildly share with those that suffer through it every single day. It's not "laziness" or a lack of discipline and determination. People with ADHD lose their jobs and destroy relationships with family and friends alike. It's humiliating and the cherry on top of the shit sundae is friends, family and every asshole on the internet accusing you of faking it. No one wants that. No one wants to learn that there's a genetic component and guess what, your kid's lives might suck too. Even with medication. Methamphetamine is not some magic cure-all. It only addresses a subset of symptoms. No one wants to struggle every day wondering why they should even bother getting out of bed because it's exhausting fighting yourself.
Sorry for the rant.
In the UK, at least, there is simply no rampant mis-diagnoses. My diagnosis has taken 2 years and this is average, perhaps quick, given the state of things.
It's easy to see why some would dismiss.
The diagnosis is sometimes unclear to people without ADHD.
This is why generally it requires a registered psychiatrist to make the diagnosis and prescribe treatment.
People with the "predominantly inattentive" subtype (previously called ADD) typically go undiagnosed for long periods, or indefinitely. I was diagnosed when I was 32.
All the school reports that say "James could do better if he stopped daydreaming|looking out the window and focused more". I was lucky I that I came out with absolutely decent GCSEs (mostly As and Bs) but unlucky in that I felt shame and now defeat that I could have done much, much better. College was a write-off, I attempted 3 times but gave in after 3 months each time because the stress caused my inastentiveness in lessons made horrendously boring stoked psychosis which landed me in hospital each time.
A lot of my life seems wasted having not known about ADHD-Pi (and of course my parents and educators), except for programming and computers which not only kept me in some degree sane (I could have been worse) but also led me into a job that seems matched to my traits and with a manager that is willing to overlook my big flaws because he thinks my skills with a computer far outweigh them.
What a journey. I say there's enough to write a book but I've just never got round to it...
EDIT: I've just walked head first into a pole just after pressing submit. Sums up my life entirely.
I'd just thought I was incurably lazy.
That is a good point, one I didn't know I was making while writing but one I agree upon having made, now that you mention it ;)
Apart from medication, I've found that pair programming has been an absolute godsend. Having another engineer next to me helps me to keep coming back to the task. We can recreate context quickly through conversation and as one of us fades, the other can jump in.
It's also helping me to realise more often when I am launching into a tangent, because those tangents will involve me vocalising the fascinating shiny thing that just popped into my head.
That said, the linked post raises a different practice: one story at a time. Context switching should be within the boundaries of a story. If it's too big, break it down.
I'm lucky to work for a company (Pivotal Labs) where this is the accepted way of working.