So it coulda been UPS what done the dirty deed! Or the driver was running really, really late.
How do you know if something is a dead short? I just read up on it and found it it's very dangerous but just looking at an electrical light socket I sure wouldn't be able to tell. Did you screw in a replacement light bulb which didn't light?
As for the pain of cutting the cord of a "perfectly good smoker", it isn't perfectly good if it has a dead short. Hopefully its replacement will be in perfect condition. When did you last contact Masterbuilt? I give someplace no more than 48 hours before I follow up.
A dead short is like throwing a toaster in a bath tub. The hot and neutral wires touching without a load. There's no way to keep the circuit closed. Every time you reset the circuit breaker it trips. My parents have a Brazilian Chandelier that has screw in tips down in the socket that can swivel over and touch the threads where the base of the light bulb screws into. They work themselves loose when over tightening bulbs and replacing burn out bulbs. When I plugged in the MES and just turned on the light bulb, I saw a flash and heard a pop and my breaker tripped. I noticed small pieces of the broken bulb glass on the bottom of the smoker that worker it's way out of the bulb cover so the bulb was in pieces when it arrived. I bought a new bulb with no problems since I put it in. The bulb in the MES worked it's way out of the socket and a piece of the wire filament holders worked itself into the socket to complete the circuit when I turned it on. Weird. I spoke with Masterbuilt for the first time this morning. I sent receipt info and pictures.