wrote
Saying that a spec of stated displacement was an indicator that the
boat in question is a "displacement hull."

Duh! And what's wrong with saying that. Every hull that floats displaces enough
water to float it. It would sink if it didn't. So every hull that floats is a displacement
hull. If somebody says no it's not a displacement hull! It's a planing hull. That's wrong.
It's a displacement hull that's going so fast it's planing. If you have a submarine it
has a hull. When it's floating on top of the water it's a displacement hull. When it's
under water it's a displacement hull weighted down enough to sink it. The same's
true for a open60. When it's planing it's a displacement hull planing. Just like the
submarine's a displacement hull sinking. Both of them never stop being a displacement
hull. So you think something that weighs tons can just all of a sudden stop weighing
anything because it's skimming along the top of the water?
Did you ever skip flat rocks across the water. The rock will skip so you could
say it's a planing rock. But it will sink when it stops so it's not a displacement rock.
As long as a hull planing doesn't sink when it stops it's a displacement hull.
Now you tell me what's wrong with me saying if a displacement is listed it's a
displacement hull? If it displaces so many tons of water it's floating and displacing.
That's a displacement hull. You lose Mister-Know-It-All.

Cheers,
Ellen