Thanks for the explanation, now I can picture the "overcut" part.

I posed a question 5 days ago regarding this and now I have my answer.  I couldn't understand how you could overcut a nearly vertical structure  that is almost at surface from 100 meters away. ( I pictured the angle as being nearly horizontal) 

I was looking at it from the wrong end. The drill started in an overcut position. Do I have it now?  I think so.