HTTP response with redirect, but without roundtrip?

Question

I want the browser to reflect some other URL than the one used to create the request, but without roundtripping to the server.

I would maybe do this:

Answer 1

No. Http is stateless, and every request has one answer. When you post, you need to redirect to a get page immediately to prevent a double post - you don't want it to sit on that post url. The redirect is what tells the browser that it is on a new page. That's just the way it works.