Absolutely not. In my standard intro material I explicitly say otherwise, tell them that actual work involves checking external references, and that I want the

Absolutely not. In my standard intro material I explicitly say otherwise, tell them that actual work involves checking external references, and that I want the interview to be as near to a collaborative experience as it can be in the odd circumstances. I also tell them that they should tell me when they're checking external resources (the CPP reference is what I mostly have in mind, but StackOverflow or whatever is fine with me) so that I understand how they go about solving problems. Because that's the actual important bit. All the coding and the questioning is a proxy for that.