Dry run over material using external offset

(40.5 is the Z bounds of 3D_Chips)
Opinions?
To avoid crashing into the material, if you move "back" to the absolute position at which the offset was cleared, with the same velocity at which the Z axis is sinking, it stays in place at the same Z height. Is there a better way that wouldn't require sending an MDI command?
 

I don't know of a way to di it without an MDI command (though you could link an MDI command to a button)
But it might be simpler to apply a temporary additional tool-length offset.(G43.1)