Perhaps you should emphasize that both buttresses crossed before heading up to the chockstone are both large and continue across the traverse. When I did the route and crossed the first buttress, I saw a second smaller truncated buttress that partially divided two chutes. The farther chute was wide and forked twice, but there was no chockstone! After descending and then crossing a 3rd buttress (2nd continuous one), I was then in the right chute to ascend.
I also took some photos that can help clarify this vague description of where to begin ascending. I'll post the photos soon.
"All men dream, but not equally. Those who dream by night, in the dusty recesses of their minds, awake in the day to find that it was vanity. But the dreamers of the day are dangerous men, for they may act their dreams with open eyes to make it reality."