Agreed.
I've got three Singers that use that cam stack. A 401 and two 500s. When I cleaned them I just popped them, I just popped the cam stack out of the machine and used a toothbrush with Hoppe's #9 to clean them. Then some alcohol to remove the Hoppe's residue and a light coat of grease, and they're good to go.
I joked with my wife once that I'd love to have an extra cam stack to take apart, but now with that link you posted I don't even need that.
Joe