I agree cushion is myth. I have had soaps that produce literally 3 inches thickness of lather and I was not impressed with them. On the other hand I have had soaps that were really thin yet gave a great shave.

I think what folks refer to is really lube not cushion. They think of thick lather as cushion and that is the issue. If cushion meant something Gillette Foamy would be king-har har.