A few years from now, we will wish we'd jumped on the 0w5 bandwagon in the "early" days.
Seems to me that oil are trending lighter and lighter. This just may be ahead of its time, like the Tucker Tornado.
The NHRA drag racing teams use 5W and even 2W for qualifying races in Pro Stock class. I know this 2 ways. I attend races frequently (going to Columbus Ohio this May) and look under Racing Oils on Redlines website.