As I wrote in my first sentence, what I'm particularly concerned about is communication - for which "clarity of expression is sometimes quite important". Nothing controversial there, I believe. Spelling and grammar aren't always crucial; but they can be.
And spelling and grammar are just the start.
Here's a line from the official, supposedly informative thread from the beginning of the 'Type 1 diabetes' section of this forum:
"Hypoglycemia is the term for when we have low levels of glucose in our blood. A blood glucose level of under 4 mmol/l is considered to be hypoglycaemia (a hypo)."
I have no great problem with the variant spellings of the key word here. But I do have a great problem with what Wittgenstein would have called the 'logical grammar' that's on display: that is to say, the appropriate use - or otherwise - of the word 'hypoglycaemia'.
Although that's far, far worse than a mere spelling mistake, I believe it's in the very same ball-park: certain people will make precisely the same fuss when it's pointed out to them - as though one were criticising mere spelling, or mere pronunciation.
Here's a correct definition of 'hypoglycaemia': "(Symptoms resulting from) low blood glucose."
The meaning of the word is AMBIVALENT: it refers as much to behaviour as it does to blood glucose.
This may not make much difference to most diabetics. But most diabetics' condition, I believe, is pretty poorly controlled. And surely the whole point of this forum is that, by means of effective communication, diabetics' condition generally might be improved.