I think you've got it right Tim. The originals probably went bad pretty quick due to the type of rubber used. Once the rubber flattens out, you will have metal-to-metal contact where a gap is specified between parts. Once that happens, the bolts aren't tight anymore and everything gets the jack hammer treatment.
I am very surprised someone has not come up with a better aftermarket design of the entire mount. Its not like its a part anyone can see once installed.
Carl
