I can't help but wonder at the hue and cry that would arise were I to suggest, in the face of a european accident board report, that the crew, and not the (say, boeing) equipment, was at fault in a terrible crash.
As to unprofessionalism, perhpas I missed something, but in the accident report that I read, the captain left the cockpit for less than five minutes (as opposed to your "half hour"), to use the restroom. Feel free to correct me on this point. If you'd like to actually read the accident report, rather than question the integrity of men ten years gone, it can be found at
http://www.ntsb.gov/publictn/1996/AAR9601.pdf
Relevant portions may be found on page 25.
As to the icing characteristics of the ATR series, a much more detailed treatment than I could possibly understand, yet alone construct, can be found in the above document. But it is my impression that transport category aircraft are meant not to have aileron hinge reversals under any circumstances, and that the NTSB's issue with the aircraft design had less to do with the amount of ice the ATR could carry than with the characteristics of the airframe's response to admittedly excessive ice buildup. I remain open to correction on this point as well.
I trust, sir, that you are not one to immediatly rise to the defense of "some" pilots, for example the the ill-fated British Chinook crew, who may or may not have been responsible for a tragic accident, but are (quite rightly, in my opinion) defended from unproven allegations of responsability, but to resoundingly damn those of an accident which even two national safety bodies cannot agree on the cause of.
Regards,
TRF