Grand Rapids Area Boardgamers
I'm having a hard time understanding why anybody would think it was eight points.
The problem is that the rulebook clarifies that the 2b affects the Keyflower scoring, but doesn't call this out as a clarification so it could be interpreted as an extra rule.
the rulebook wrote:
All of a players (sic) transport capacity and upgrade ability is doubled. If a player has the Keyflower boat at the end of the game, the Keyflower scoring is doubled.
One could interpret this as "2b doubles the transport capacity, and also doubles the Keyflower's scoring of that doubled capacity" for a 4x multiplier. It's got to be intended as a redundant clarification, though, to make sure people know that 2b does affect the Keyflower scoring as opposed to the Keyflower scoring on the base transport capacity.