Juli, I'm sorry this thread somehow slipped between the cracks.
No, you don't have to limit yourself to removing only one-third. You certainly can do a severe pruning and reshaping of a shrub rose. Just be sure that it's late enough in the season so that you won't get more frost soon after you prune the rose bush. You don't want frost to damage your tender new growth.
In view of your experience with Chuckles, it's highly possible that DayDream is still alive and is simply later than usual in displaying signs of life.
