Its called the theory of evolution because its an explanation of an observation not because its an untested thought experiment. Anyone whose point hinges on "evolution is just a theory" is a fucking idiot.
How about you tell my why its called "the theory of electricity". Just because its called a theory doesnt mean we dont know what electricity is.
Explain electricity, since "we" know what it is?
What? Electricity is the movement of electrons across a conductor. Point please?
Yes, another vague definiton for a very mysterious force. Does electricity exist without a conductor? If so, then your definition is lacking.