Sitstart under the exit prow of Bicarburation, traverse under the roof with pockets, continue on the ledge to the final jug of Bicarburation, do not mantle (for resting) and go back in Bicarburation straight after reaching the final jug and exit above the starting point, without using toe hooks on the lip of the roof, the 'doorposts' and the walls.
NB: many variants have now been climbed and all kinds of new combinations are possible; we've decided not to publish all of these and stick to the most logical lines.