But that's "To be or not be twice".

Right, I'd interpret that their specification was "Two 'b' or not two 'b'". In that case their code is wrong. For example, "ab" is not two 'b's, which means the second boolean condition evals to true (ie., it meets the specification). However, it does not match /(bb|[^b]{2})/, so the code is wrong.

And if they did, that can be shortened to: /(.{2})/

No, because that is highly political code. It says something without expressing any meaning, and is completely interchangeable for a lot of situations.