I agree except the coil is a tiny little thing where as a battery is pretty large. By the way - have you ever had a coil weld it self to the gas tank? I have, when the tank rubbers failed and my aftermarket coils (which sit too high) shorted against the bottom of the tank. Thankfully it wasn't a big boom as the tank was filled to the brim with fuel. I noticed it because vapor was pouring out the cap vent like steam out of a kettle. Ideally you want as few things under the tank as possible just due to packing constraints, it probably isn't a good idea to have too many open terminal electronics under the giant metal thing filled with fuel.
I do agree lucky is over reacting - most cars have electronic fuel pumps and the fuel gage sensor in the tank and both of those things are electrical.
