The "On" I refer to for me, is the point at which a sailboat comes alive. This can be as subtle as the first hints of the boat making way when sails begin to pull. It is in fact about the motion on a monohull for me. The heeling, even just a few degrees, is what puts it on a track of sorts. Without that track, there is no ON.

Instead of speed floor and it's relation to a planning speed, for me, sailing is the state I reach after the boat is ON. And that takes care of the planning speed, because that point in time, the ON, is my destination when it comes to sailing.

From there, "cruising" may mean I have to go faster to get to the next point on a chart. I guess that's why I try to sail even if I have to get somewhere.

Many a good sail has been spoiled that way for me.