Thanks for the post and video link. Yes, Riva has a different ways of doing a few things. When I got my boat I was concerned as well but after using their lift system I find it superior. It is a very nice advantage to being able to lift from one point. The points of support are on the stringers and keel and are perfectly balanced for the particular model. Riva's are not without their weak points and they too are getting to be "old" boats. My 1959 had stress cracking in the stringers where the rear lift points attached. I had to sister in some oak support to the original stringers to make it 110% solid.
Make no mistake it is a very solid affair and is pretty cool.