ATRs do fine in ice as long as the pilot is smart about it... just like any other airplane. You have to escape the conditions at the first signs of severe ice. Of course, our training on icing has changed significantly for ATRs post Roselawn.

I got so much ice on an ATR-72 once, I had a 4 inch rams horn on the ice indicator probe. She flew fine, but you'd better bet your life we ran the severe ice procedure and got the hell out of it asap!

In Roselawn, I think it was indeed a chain of events. An airplane that had boots that were too small and a tendency to develop aerodynamic flow distortions over the control surfaces in ice accretion (unknown at the time). A lack of training in icing procedures and severe icing escape guidelines for the pilots. And finally, inattention by the pilots to their deteriorating condition, as they held for an extended period, in freezing rain, at flaps 15.