I applied for a job (I think it was HP) while I was in college. A year later, I received a form letter that they had filled the position but would keep my application on file. Sending a form letter like that so late was probably worse than no response.
I just realized at least I'm just dealing with emails. Not sure what's worse than getting a letter after all the effort on your part sending letters. I've applied to something like 120 positions so far this year, I've lost count, I spend about 1-3 hours each weekday morning writing covers and such. I couldn't imagine sending that many physical letters per day.