Well I have to give him a nod for trying, from a design stand point I'm surprised it actually worked. The amound of stress put on that "ring" is HUGE. Not only does it have to deal with compression forces from the mast, but now it needs to deal with torsional loads from both the keel and the mast! I can only sit here thinking of the bearing set up and scratching my head. The other thing thing I wondered about was groundings. With this design the entire keel is held into place by a singe ring of steel which is attached to the boat by bearings and some sort of race/gland. this makes for a very small attachment point not to mention that there is NO keel stub. With centerboards there is at least the reinforced trunk.
One last thing, while this might be a pretty half baked idea for a mast/keel combo, it makes an interesting idea of a less stress inducing canting keel. I really don't know too much about it, but it seems that the main weakness of the cantings are their central pivots with hydrolic rams. With an external ring the entire boat would be a bearing. there is still the issue of the force required to move the thing, so maybe it wasn't a good idea afterall...
And what's with all the French bashing, they make some damn fine tris! Go on youtube and look for videos of those 60ft maxis charging though the waves at 40kts. Makes me drool a bit.