quote(A voice coil is an electromagnet, right? )
answer= no actually it does not use magnitism like people think, most people think is does the north south pole thing but they actually use what is called the right hand rule of electron flow. which i do not have time to explain, but it is not magnitism.
quote (. Let's face it: a 1 ohm load ain't got very far to go from "normal" to a "dead short". )
answer= think of it this way if you take 8 ohm how many times do you have to divide it by two to get to 1 ohm, then take 1 and divide it in half and see how long it takes you to get to dead short. you will be there for awhile because it will never actually reach 0. ohms does not mean anything just like the + and - on a speaker do not mean anything, they are just reference. instead of saying + and - on a speaker it could say apache and skater , you can still hook it up correctly.
Quote(whereas an 8-ohm speaker in heavy clipping could drop as low as an ohm or so )
answer= as per my previous answer you can build the amp to make the same power at what ever ohm you want. years ago they picked the ohm rating we use now because of the length of wire and ga. in the coil that was practical to build and then they built amps to work at that ohm.