To sell your good a consumer must be both willing and able to pay. Under this system that would be the 2X price since he doesn't know which price he will actua

To sell your good a consumer must be both willing and able to pay. Under this system that would be the 2X price since he doesn't know which price he will actually get (if he knew ahead of time, or could back out of the deal after learning the price, you'd always be giving them away). There's always going to be less people you can afford 2X than X.