Found this on road bikereview forum
"Ernesto he had 5 sets of these cranks made for a time trial bike for Tony Rominger. The right crank and chainrings are made out of billet and are therefore one piece, without any chainring bolts. The whole set-up is super lightweight."
cannondale did something very similar, quite a few years ago
cannondale did something very similar, quite a few years ago