I'll either be running Blacks or helping Puffing Billy with organisation.
Would love to have a bigger Steam Bunny mass 3000 attempt. The more the merrier. I would say a sub 9 hour crossing is entirely achievable.
Having given it some thought (I am going through the cross, disappointed phase of all failed adventurers at the moment), I would say a better route is to start V early at Pen Y Pass, go easy up to CG, take CU and YW, run down railway track as far as Clogwyn and then cut straight down to Nant Peris. Taking the train up to YW makes you start too late.