It would be fantastic to see Sidney Crosby return to the NHL, but I wouldn't want that to happen under any kind of a cloud. If there's a chance that they can correct his soft tissue injury, then a comeback would be very welcome. If this is some sort of strategy to minimize the risks and give him a clean bill of health when he might not actually be completely healthy, then I would say that he should retire.
There is simply no shame in retiring from hockey in order to avoid death or a life-threatening and severe injury. It's just not worth it.