Actually, I have a couple of very well ranked pages, although they're on pandalized domains. These pages have more content and more uniqueness when compared to other pages on these sites.
I've had the same experience.
Why Doesn't Panda Run at the Individual Page Level?
It does for really good pages, but the reason it doesn't for average pages is because Google has assumed responsibility for all pages a user visits after clicking on their SERP links instead of just the landing page.
I agree it seems draconian or extreme, but it's simply their old principle of penalizing links to bad neighborhood websites applied to the domain. A weak page on your site is the same as a bad neighborhood on your site.
Change your internal linking structure by removing links to bad neighborhoods or irrelevant content, and you might see some progress. That's a quick fix. A more demanding task is to develop the existing pages. If you don't have the time, you can just noindex, no follow the weak pages.
Incidentally, I've noticed on the opposite side, links to good pages/sites actually get some Panda credit, which is actually reasonable and logical.
Quality links (internal & external) and quality content (unique & not shallow) are the nuts & bolts of user experience, and Panda, the simple animal, simply focuses on them.