All I know is that noise in a stereo is ignition noise...
I didn't notice any noise in the radio while it was like that, so I think you may be right about it blocking harmful interference TO the ignition system...
I need new wires (the Magnecores are getting pretty dirty, and have at least 30,000 miles on them)... but I'm waiting for that Accel coil to come out on SP and change it all at once.
Oh, and my spark plugs... they looked very normal when I pulled them out.
