Not only that, but Guests can use hints, giving them a several second advantage.
When I play offline to warm up, I have to solve slowly and sit around after I'm done, to make sure I don't set a record. Even then, sometimes I get in one second faster than the record. It isn't fair to the person who set it for real.
If Guests don't compete, why should they be able to set records? I see no problem with displaying their time for them to see, just don't save it.
Slotted spoons don't hold much soup. - Stephen Sondheim