He broke the rules, as others had done.
One can see where you are coming from, but to knowingly break the rules when you had absolutely nothing on your side to justify breaking said rules, I mean they never ever sighted Mt Erebus, just beggars belief.
It was stated in an earlier post that Jim Collins was a good pilot and a decent man, and I would agree with that. But his decision to descend when he did, with the info he had regarding weather conditions as they were must surely be regarded as a massive brain fart, and if he could come back and join this discussion I am sure he would agree with that opinion.