Indeed, I personally quite often get stuck on some things. I put this down to typing from morning until night. Sometimes even the most basic words catch me out.
For instance, only the other day I struggled to not only think of mountains but spell it too. I also find myself doing some sort of habitual/repetitive typing and words when they're not relevant.
As if my hands go into their own world and just type extra-familiar words. Such as for example, serve - she likes to serve, there's times I write server instead.
Or just familiar words but not quite in context. I think that for myself, it's literally just down to the scale of typing per day.
I rarely make spelling mistakes though and I can see it's confusing for people with online crap.
I also find it difficult then to decipher what people mean.
I.E
been/being, your/you're, of/off their/there/they're.. (and a hell of a lot more)
I find it increasingly difficult to understand what people are saying as this is becoming far more commonplace and makes it quite hard to do things as I have to then spend a bit more time trying to work out what it is exactly, they're trying to say - slows me down.
xx