A B777 CREW; DSNDING INTO EWR; UNDERSHOT ASSIGNED ALT.

Narrative

DURING A DSCNT TO EWR; ZBW ISSUED US A CLRNC TO CROSS 20 MI N OF SAX VOR. THE FO WAS FLYING THE ACFT AND HE PROGRAMMED THE FMC TO CROSS 20 MI N OF SAX AS CLRED. THE FO CHOSE TO USE THE VNAV FEATURE TO COMPLY WITH THE CLRNC. WE LEFT 16000 FT AND THE VNAV FEATURE APPEARED TO DO WHAT IT WAS DESIGNED TO DO. DURING THE DSCNT; I NOTICED THAT THE 'MATH' DIDN'T COMPUTE TO MEET THE XING RESTR. I THEN SUGGESTED TO USE THE SPD BRAKES TO EXPEDITE THE DSCNT AND TO DECELERATE TO 250 KTS PRIOR TO PASSING 10000 FT. FO PROTESTED BY SAYING; 'THE MACHINE WILL DO IT.' WHEN IT BECAME OBVIOUS THAT THE RATE OF DSCNT WOULD NOT COMPLY WITH THE XING CLRNC; FO BECAME FIXATED AS TO WHY THE VNAV FEATURE DID NOT WORK AS PROGRAMMED. AT THIS POINT; I FULLY EXTENDED THE SPD BRAKE TO INCREASE THE RATE OF DSCNT AND DSND TO OUR ASSIGNED ALT AS RAPIDLY AS POSSIBLE. IT IS PAINFULLY OBVIOUS THAT TOO MUCH EMPHASIS IS BEING PLACED IN THE AUTOMATION AND THE BASICS OF FLYING AN ACFT ARE BEING ABANDONED. THE CONCEPT OF AUTOMATION SHOULD BE CONSIDERED AS AN AID INSTEAD OF THE PRINCIPAL MODE OF SAFELY OPERATING AN ACFT. COMMON SENSE IS RAPIDLY DWINDLING.