i ran into a set of these the other day, and have found one bit of info from the net about them… i wonder if lemond used these in '89? speedplay site museum has them as an 89 item.
i think their big feature is adjustment of right and left float independent of one another… so you can float 2 degrees in and 4 degrees out on one foot, and 0 degrees in and 5 degrees out on the other… not sure why it would be super useful, and they be heavy… v heavy. anyone remember/used them?