I presume you mean Transgenic?
Essentially although that boulder is a pain in the arse (no pun intended) if you use the correct beta you end up moving upward away from the block to a hold in the crack before rocking up on an extremely tentative heal smear to get the break.
Incidentally this problem used to have two variations: The first used a dubiously attached foot block at the back of the roof and to the right of the central tree (Ft7c+/8a), the other variation omitted the block (tough 8a). Now I'm not sure which version you were trying but the former variant is no longer possible because as of last week Gaz Parry removed the now very wobbly foot block. The good news is the harder version inevitably keeps your feet higher and thus keeps your arse away from the big block... bet you're sorry you asked.
G
