The article Convenience and Its Discontents: Teaching Web-Scale Discovery in the Context of Google had some great observations about information literacy. I agree that single-field discovery searches might be an improvement over database-hopping, but anyone who uses these frequently will tell you that they produce very uneven results. Discovery may LOOK like Google, but when it does not produce Google-like results, students retreat back into the familiar, and any lesson in information literacy is lost. Information literacy is not intuitive, and I think that scholars (and… librarians, too — gasp!) forget that what they see is not what an inexperienced user sees. Pointing out the contrast between discovery and Google, and instructing/guiding students through the steps of making a discovery search work for them, seems like a terrific way to approach the issue.
Also, I LOVE the pizza vs. research sources metaphor. I think I will use that in my own info literacy workshops!