I don't know, but looking at the pic closely and re-reading their email - it looks to me like they did both methods of connection. It looks like they installed a clip and then pressed the pins. To me it looks like the pins are, in fact, slightly mushroomed right at the surface of the clip.
Seems like overkill to me, but I doubt that the clip or the master link will be coming off anytime soon.
Easiest way to tell would be to remove the clip (it should pop off with minimal force using a flat screwdriver) and try to pull out the master link. If you cannot get the master link out, you are good to go. In that case, I would replace the clip to take up any slack in the side to side motion of the master link.
just my $0.02
Seems like overkill to me, but I doubt that the clip or the master link will be coming off anytime soon.
Easiest way to tell would be to remove the clip (it should pop off with minimal force using a flat screwdriver) and try to pull out the master link. If you cannot get the master link out, you are good to go. In that case, I would replace the clip to take up any slack in the side to side motion of the master link.
just my $0.02