alt Hacker NewsNot at all. It's called learning computer science. Just like you can do calculus without simulation, you can understand the semantics of a computer program without running it. It might make it harder, but running it is only a didactic tool - as Knuth did, you should be able to prove it correct without ever running it.
Yes but not everyone learns like that. Some people need to feel something before learning the theory. It makes the theory easier to digest.