The answer to the password question is just crazy. The correct answer is "Yes," for any migration scenario I can come up with. Even if it's a completely new system, you can set up your account at the first login to use the same password.

I have no idea why he was talking about TCP/IP. It is utterly irrelevant to end users of email systems. Only networking experts, and by that I mean people working with data-center-sized networks or very specialized networking software or very large-scale connectivity problems, need to think about TCP/IP.