{HEAD ~ The largest distance} of any focus point from {TAIL ~ the best fit surface} is then identified and compared to a predetermined maximum distance value 
{ HEAD ~ The largest distance } of any focus point from { TAIL ~ the best fit surface } is then identified and compared to a predetermined maximum distance value
HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH