Thanks Will. It wasn't the cold alone that finally got my W.robusta, it was the moisture. My cap blew off in a bad storm and snow and ice gathered in the crown and it was all over after finding it a few days later.
The word is out that this palm is hardy to the low 20s before it expires (Gibbons & Spanner) but some will say they have survived colder and Im sure they have but duration and moisture would have played a very important part. After growing them for almost 2 decades you do see a lot from each winter.
Personally I think several hours at 22* will kill this palm unprotected. There will come a time when they can outgrow normal and easy protection care and for that reason its nice to have one coming along, several years behind