Photos might have helped.

You may have sacrificed this new growth needlessly.

Jeri

what Jeri said.

I forgot to add that the new growth was unusually soft and water-filled--much more than ordinary new growth--and that the few leaves there were were small and VERY far apart--like, three tiny leaflets on 15" of growth. Does that change things at all?

You can't reverse time and change having cut it off, but if it had been me, I would have waited. Alot of times when my roses put out new growth, it will look red, kind of limp and different from the rest of the bush. Sometimes that just happens.. Dont worry though, it will grow back.
Maude

You should have posted pics before cutting it all off. It sounds to me like it was probably just normal new growth. All roses have their own look when they produce new growth. Much of it is red and soft until it has time to mature. That's why they call it "hardening off" when it matures. New leaves are often crinkled until they grow out and green up too. You need to be patient and observant to see how each of your roses grows normally so you'll know when something is different. And don't compare one variety to another. They all have different personalities.