I wrote a little pin out program and read it with a frequency counter. With a good calibration value for a 4MHZ clock, the pin frequency was 97.48 KHZ.

With a 12F629 PIC that lost it's calibration value, using OSCAL $80 the frequency was 115.35 KHZ.

Changing the OSCAL values yielded:

$70 = 112.25 KHZ
$50 = 105.04 KHZ
$30 = 98.40 KHZ
$2D = 97.40 KHZ

So OSCAL = 2D to get this particular chip back on frequency. Debug is working again.