FT817 sensitivity

Today I checked the sensitivities of my FT817 and FT817ND using a loaned signal generator. Although about 10dB deaf at 472kHz (expected) both were easily able to copy down to -127dBm on CW on all bands to 70cms. -127dBm is as low as the generator would go.  I could have added a 10dB attenuator, but did not.  I also managed easy access of GB3PY and GB3OV 70cms repeaters at the 500mW level into the V2000 vertical.  My conclusion is things are OK at my end and I wonder if G6ALB has some additional cable loss at 70cms at his end (water in the feeder?).  My antenna has been up for about 2 years whereas his has been up for around 20 years.