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And how exactly can someone master complex tasks while failing at basic fundamentals?
There's Genius Ditz for when someone is really, really competent in one specific thing and incompetent toward everything else.
^^ That's what makes it comedic.
^ Yes, but here the incompetence is only for the simple parts of the specific field, they can be competent in other areas.
@Star Tropes: arithmetics and algebra for example involve different mental paths, so there are people even with dyscalculia that struggle to solve the simplest addition but are still successfull in maths: https://www.learningsuccessblog.com/blog/dyslexia/dyscalculia-awardwinning-mathematician
I Don't Know Mortal Kombat is the closest thing I can think of.
It's about characters who are skilled at something like professional boxing but can't win a fighting video game. Though it doesn't have to be exclusively about something hard being easy and vice versa
More generally, see Idiot Savant.
A character has difficulty with something easy, but finds it easier the harder the activity or subject matter gets.
e.g.
Alice can't add 2+2, but can resolve differential equations in her head.
Bob gets seasick on a perfectly calm sea, but put him in a storm at sea and he never loses his balance even standing on one leg in the rigging.
Charlie can't peel a banana without setting the house on fire, but can make a 5-course dinner with half an hour and an empty fridge.
Daniel can argue Shinto philosophy in literary Japanese for hours, but answering a yes-no question in Japanese takes half an hour because he can't pronounce them.
Ed can kick a field goal so it bounces twice against each post before going in from two fields away, but ask him to toss a ball to someone five feet away and it ends in disaster.
etc, etc.
Edited by Chabal2