Yup, that’s one of the ideas behind this, that long term you’ll be able to update a MeshPart while keeping the origin point in place.
I don’t know at the current time if we’ll be able to do that initially (it may have to wait for the Mesh workflow improvements that we’re doing this year), but even if we can’t, by having the origin information available through the pivot you could easily write a plugin to get that kind of rapid prototyping cycle.