YES, I'll start a real flame war here but I am serious about the
question.
HK says a cutaway transom allows the boat to drain if it is swamped,
seems sensible.
The designer of my Tolman says to have a high drywell in front of the
motor on a cutaway to make sure she does NOT fill with water.
A compromise seems to be to have the dry well but also have serious
cockpit drains, not the tiny ones you see on most boats, I mean at
least 6" diameter AND have the cockpit drains with flapper valves made
of thick rubber sheet attached to the transom with SS screws. This
would require the boat be decked with floatation underneath.
I am curious because I am considering in the long term what boat to
build next and am considering a modified 23' Tolman Jumbo with more
deadrise.