Start directly below the break in the twin roofs that mark Tits 'n' Ass, rather than climbing up the ramp to the left: climb up over large blocky ledges (with small trees growing out of them to the sides) to a darkish bulge. Pull directly up and over the bulge (watching out for loose rock underneath it), then continue up the face to the notch in the roof, and finish as per Tits 'n' Ass.