Getting bottles in that hole as it is now would be interesting. I foresee a project coming on...
:)
Would make sense to dive it from the east workings rather from under the caban.
The connection's shown on the map and if you stare into the water for long enough, I'm sure you can just make out the top of a tunnel at the bottom of the last chamber in the east workings. Slight climb up into that last chamber but still easier than going in under the caban, I'd imagine. According to the map, you wouldn't even need to go to the end chamber... all of the chambers west of the Townshends chamber are linked by the drive which connects to the chambers behind the caban.
I'm sure MarineBoy was talking once about diving the connection, though I don't recall if he ever did.
If someone wants to dive it, I'll happily come along to haul their kit!