Thanks for the great comments and for attending the seminar. With regards to sitemesh, the performance hit is actually (amazingly) minimal, hence it’s popularity. It does some special tricks, it actually wraps the “real” response object in a sitemesh one that uses a StringBuffer instead of writing directly to the response.

So in terms of the developer they “think” they’re wriitng to the response, but you’re actually just building up a string which sitemesh then includes into the real response later.

PS We’ll have to agree to disagree on GSP