I now have 2 B68s with the Selle Anatomica upgrade. My sit bones put me either on a poofy saddle or the B68. I was hoping that I was wrong on my sit bone measurements, but now that the Brooks are broken in, I can measure the distance quite clearly. I'd like to ride a normal person's saddle, but, nope, ain't gonna happen.

As for the selle anatomica slot....I put the saddle onto the trainer, first. Over time a little judicious use of sand paper fine tunes the cutout so it doesn't pinch. I also drilled some holes into the side of the saddle so I can apply tension side-to-side.

You should also have found the review by the person who sent their B68 to selle anatomica and shortly there after the frame broke. Interestingly, the second saddle I sent to them came back with a different slot--a little shorter and away from the rear portion of the frame. Works just as well as the first.

But, I need the cutout and I think it works pretty well. Time will tell whether this will affect the lifetime of the saddle.