Mark,
I believe you're right about Hankley Common rivaling Walton Heath in abundance of heather. It too was the subject of a large heather restoration project. Interestingly enough, the current course manager at Walton Heath, Ian McMillan, was the course manager at Hankley before moving on to Queenwood.
At Hankley Common, Ian, if memory serves me correct, was very involved with the removal of trees and the restoration of the heathlands.