I understand your argument, but don't get sucked into defining boat performance by slip length. If you take comparable boats of similar performance, displacement
, carrying capacity the one with the raked bow will have a greater LOA
over the plumb bow version, but very similar LWL. Sitting static, level in the water, the the submerged sections of the bows of both boats displace an amount of water equal to the weight of the bow. If I throw 500Kg of stuff into each forepeak, each will have to displace an additional 500 litres at the bow; the plumb bow is going to go down further than the raked bow. Therefore the plumb bow has less reserve buoyancy.