My advice is 2 portions of Chivas Regal 4 hours before the interview and then 2 full bottles of The Famous Grouse and Blue Label, 15 minutes before. Then, let it flow. If they don't get that you are a good tech guy, move on, they don't deserve you.

Now, I've had a few strange things myself with interviews. Except for the company I ended work for, all other were a disaster. Everyone from HR knew 0 about Linux or programming. One guy was really dumb. We talked about bash for Linux and at the end he starts reading his notes and says "Sad you did not talk about scripting in Linux..." and I just went "Ok bye bye".