Overriding methods in Swift extensions

Question

I tend to only put the necessities (stored properties, initializers) into my class definitions and move everything else into their own extension, kind of like a

Answer 1

Extensions cannot/should not override.

It is not possible to override functionality (like properties or methods) in extensions as documented in Apple's Swift Guide.

Extensions can add new functionality to a type, but they cannot override existing functionality.

Swift Developer Guide

The compiler is allowing you to override in the extension for compatibility with Objective-C. But it's actually violating the language directive.