As far as I am aware, Bentleys starts from the holds at the left hand side of the lip, as does Captain Hook. Captain Hook then traverses the lip to the arete, hanging under and using the undercut/ sidepull on the way, then up the arete, which is steady once you get there. For Bentleys I made one move to the right, then locked to the high white pebble with my left, held this and got the dish with my right, then battled, swam, and kicked to a standing position, and easy walk up the slab. So pretty much a straight up problem, with no arete used. I expected holding the pebble and reaching the dish to be the crux so I was sorely disappointed when I got there and fell off several more times from the thrutch. But then I am crap a mantels.
I think Bentleys originally used a lower pebble for your left, but this snapped and I don't think I could hang the resulting divot/ scar, as suggested in the guide.
Were you trying this on Sunday? because thats when I did it.