Goodness there are some real issues here with the 'Latin' types (as so perceptively pointed out previously). Saying the aircraft took off and landed safely so where is the problem doesn't cut it. The guy got lucky. Next time maybe he won't be. We're not in the business of being lucky, we're in the business of being safe. Is it a rumour? If you listen to the tape I'd say it's pretty much a fact the guy had snow on his wings, unless you think LTD was making it all up and lying to Boston ATC.
This thread is spookily similar to the one on te TAP A310 flyby. Anyone impartial can review the evidence for what it is and see the implicit failings, yet any response from Spain, Italy or Portugal is limited to attacking the original poster, questioning his truthfulness and generally trying to hide from the facts. One can only hope that sort of attitude is not indicative of the industry as a whole in those nations.