Well, that would be desired behavior. I've recently learned that PHP pages don't send the proper cache headers by default - so I'm going to be manually adding them based on updated information. So if the page is updated - then it will send a new copy. If it's not updated, it will read from your cache.
The only way to achieve what you're looking for is to have it cache per session, and never show you updated versions unless you manually hit shift-refresh or close your browser and re-open it.
Since these pages are dynamically generated based on new content, the method I'm implimenting will make the most sense. - if it's updated, show new content. This will speed up refreshes for pages that aren't changed, like posts you've already read and things like that.