The pitch quoted from the post I was responding to essentially said it was going to siphon all the business class fliers from normal flights: "Give those passengers a supersonic plane, cut the flight time in half, and charge the same price." There's no way businesss travellers would choose subsonic travel if supersonice was the same price for half the time.

We agree I think that there wouldn't be a similar price between the sub and supersonic travel options. The economics of running the routes can't work out to a similar price to existing offerings.