> The thing is, unlike what most retired engineers you'll meet here
> think, it doesn't merely take mathematical intuition. It takes much
> more than that. This is physics.

I STRONGLY object here. Physics is entirely mathematically
understandable. It does NOT require any special qualities beyond common
sense and mathematical abstraction power.

Let me tell you this. Einstein has a special reputation among
scientists (especially physicists of course). Einstein is revered as
someone with unreachable high intelligence and intellectual
capabilities. His brains are on formalin somewhere. It's considered
more precious than diamond. This is because people do not understand
Relativity. It is beyond their mental powers. Einstein did comprehend
Relativity though, because he invented it. So Einstein is revered as
someone who is really superior. This in contrast with for instance
Newton. All what Newton discovered is within the reach of everyone with
a little bit common sense. If you master all what Newton discovered,
you can put yourself on equal level as Newton (forgetting the fact that
discovering things like Newton did is far more difficult than learning
them). This will not work with Einstein. People cannot see themselves
at the same level as Einstein, because they do not (really!) understand
Relativity. Okay, they can apply the rules (of which some are rather
"tricky"...).

The fact is however, that Relativity CANNOT be understood by common
sense (this follows immediately from your words "this is Physics"), not
because Relativity is too difficult, but because IT IS NONSENSE.