On 24/07/2015 10:57, Janet wrote:
The solution is to cut out ALL reverted (green) growth as soon as you
notice it; prune right back to a variegated stem, behind where the
reversion occurred.

Not just variegated. My corkscrew hazel keeps producing healthy straight
shoots, and I keep cutting them off. Seems kind of cruel to cut off the
healthy bit, and leave the diseased corkscrew part.

At least, I assume the corkscrew is a virus?

Andy