JP,
Not quite sure what the difference is between the incident you describe yourself as encountering and what probably happened to ZD576 but what really confuses me now is
"More important perhaps, who said the Chinook's entry into IMC was inadvertent?"
So you are trying to tell me that when you did it it was OK as it was inadvertent, a mistake or as you say something you had not planned to do but, in your opinion the crew of ZD576 planned to deliberately fly in to IMC?
How on earth can you arrive at that conclusion?