Think about it for a minute. The purpose of a JSP (or any other
servlet) is to compose a (usually) HTML page
on the server to send to the client.
So what is happening is that you are causing the server to needlessly take a longer time to compose the response, which it then sends to the client. (There are buffering issues that take place as well, but that's orthogonal to the primary issue).
So what exactly are you trying to do?
hth,
bear