I thought I’d post a sample (apologies for the full-on subject!)
—N

If your designer’s instinct is telling you that these fonts work well together as you intend to use them, and not that you like this one and that one so you’re going to use both, then by all means, go for it.

Your sample requires some sort of registration to view.

The above link should work now! not sure what the other problem was…
—N

Nicholas,
Is it ever okay to mix two serifs? Yes.
Can it be done without some consideration? No.

The contrast is hard to take in given the size differences. It will take someone with better eyes to tell you if they’re working or not, but I can give you a bit of hope. For every rule concerning what can & can’t or should & shouldn’t be done with type, there are many exceptions. If you’re interested and haven’t already been through it, Bringhurst has a chapter on choosing & combining typefaces in The Elements of Typographic Style. In the forward to the book, RB writes “By all means break the rules, and break them beautifully, deliberately, and well. That is one of the ends for which they exist.”

What is the font size for your body text by the way? Could just be my display or perhaps I’m just getting tired, but it’s pushing the limits of legibility on my screen.