Resenting Radicchio

How can food that looks this good taste so bad?

Relatedly, have you ever thrown a dinner party where the major topic of conversation was how bad the vegetables tasted? Where, a week later, the guests still wanted to talk about the absurd inedibility of what you'd served them?

I know, I know, fool me once, shame on the chicories. Fool me twice ... well, I'm not sure why I thought roasting our two heads of radicchio and one of endive would come out less bitter than the last time we tried.

Epicurious's blogger had a similar experience with her CSA radicchio:

I assumed that this new radicchio would taste like its more familiar counterparts (a little crunchy with a gentle, palatable bitterness), but what I got when I bit into a leaf was pure bitterness. I had to spit it out. ... With a lot of parmesan cheese and some pasta, the radicchio was rendered somewhat edible. There was still a lingering bitterness that made it difficult to eat a lot of it but at least it didn't all go to waste.

Help? How are you guys eating this stuff?

P.S. At some point in the meal it began to seem like a good idea to start a Twitter account by what one friend called "very angry lettuce."