RacerX, sure have. they get internal windings layer shorts, making them change the amount of delivered voltage and signal to make the things continue to work.
Worst case scenario is where the coil gets a jolt of serious voltage from a spike, then layer shorts, makes the module overwork to keep up with the damaged coil's requirements to do its job, module failure becomes cronic and then peolpe hear how bad this or that system is, when all the time it was a damaged coil settin the entire system into chaos.
The Super Stock round series coils from Accel are OK for Cd and HEI useage, wound to work with both ballast resistor for point and low output stock replacement ignitions, like Pertronix and Unilite, unresisted HEI, MSD, other CD systems.
Super Coil is only inte4nded to be used for point and maybe Pertronix, Unilite WITH the reisitor in place, and in some apps, the added resistor sent with the Super Coil also.
Over the years, many parts people have started many wive's tales about useages of some parts, and this has even trickled back to some tach lines within manufacturer's houses, making the tale into fact, only it doesn't work that way, most situations.
Super Coils are also super sensitive to temperature rising, heat well-up and resistance within their electronic environment, and can do some strange things when allowed to get overheated. Some things colis do just make engines run crappy, not all coils go away and stop the car. They can simply produce some strange symptoms, like carburetion off, strange timing curve changes, overheating, and more.
Super coils like being mounted nose up, like all other oil filled coils, to ensure the windings are fully covered with heat transfering oil they are filled with. Mounting the coil on its side or nose dwon,can expose the windings partially to the air vloume inside them, coil and system (module) overheating and failure may well result from this incorrect mounting.