Are you sure you are quoting me, Sir?
I did not know the DME arc is 12 miles but you may be right. I still don't know if he was approaching 30 or circling for 12. The charts we have here are all for 30. I was hoping someone could find the circling approach to 12. I know there is the back-course (back-beam?) to 12.
I am sure he got a terrain warning -- maybe right after ATC warned him. He apparently said he had the field in sight. He should have been looking at the Margall hills on his right! But we know what happens. Your first reaction to the EGPWS is disbelief (so it must be a false warning); then you wait another five second almost frozen; then you execute an insufficiently aggressive GA and don't clear the ridge-line.