A similar story, which I've posted before but, I think, to aue. I
had a college fraternity brother who was from some suburb of Boston;
it may have been Attleboro. We would ask him to pronounce "park",
"pack", and "pock". To us, they all sounded the same when he said
them. He insisted he was pronouncing them differently. Maybe he was,
to local people.
Incidentally, I am from the South and neither I nor any of my
relatives pronounce "pin" and "pen" at all alike. I have gone to
school with and worked with people from all over the South, and
though I believe I've heard that pin/pen equivalent accent, it's
certainly not common, at least, not among city folk.
--
John Varela