In the UBL system, X & Y can be used to specify the starting location of an operation. That can be automatic probing, manual probing, invalidation of mesh points or editing. What ever the specified X & Y location is, the nozzle is moved to the closest mesh point to that location (not necessarily that location).
With a G26 Mesh Validation Pattern printed on the bed... It is easy to edit any given point because the nozzle will move around and show you which mesh point you are editing...
With a G26 Mesh Validation Pattern printed on the bed... It is easy to edit any given point because the nozzle will move around and show you which mesh point you are editing...