Haven't used it in a while, but I did have one page that was indexed in inktomi, and ink followed it. It still listed the old url for a long time. I finally put a server side 301 redirect on it, it still listed the old page for a while, then after a few months, it started listing the new page. It still requests the old page, however.
I'm not for sure, but my thinking is that google will not obey that tag, I do see it checking the 301 redirects from the server, however.
Having said that, I realize that's not your question anyway. When you mentioned 'refresh rates', that's what everyone responded to. Did you mean (meta) refresh tag, or do you want to respond with 400? Or did the page get deleted, in which case you want a 404 error?
* 400 Bad Request: Impossible request or syntax error.
Probably, you want a 304 response:
* 304 Not modified: Use the local copy if you cached it. Often seen when using the HEAD method, rather than the GET method.
Unless you did change the page, then 200 OK is what you want to serve.
When you say that it's 'Set at 200', do you mean that you send non-parsed-headers? Normally, the server will deliver a 304 or a 200 response, and both are perfectly acceptable.
//Hope I understood the question correctly ;)