<<An incorrect range generated by CPLS could be just a dangerous as one generated by TANS.>>
Not really - Flt Lt Tapper was well aware of the potential inaccuracy of the STANS of the time - I have argued for a long time that they would not have relied upon it as close in as waypoint change.
The CPLS system interrogates a (back then) PRC112 which was effectively a portable DME - intrinsically reliable and the range very accurate (if you were getting a return and it was of the right order, you would expect it to be very accurate).
But it had to be where the pilot was expecting it to be - not 1/2 mile or more further up the hill.
It was more than just a range thing - don't forget you could home in on it (you got an approximate bearing) and with their oblique approach to the coast, this would have accounted for the track they took on that last leg.
Just for academic interest, has anyone here ever used the air version oif the Clansman (340) for VHF homing in a Mk1 Chinook? - How was it?