[DFDL-WG] Can I prevent data from getting into the infoset?

Suppose I have an email address with 3 parts, a display name, a local part, and a domain. "James Garriss" <jgarriss@mitre.org> Display name = James Garriss Local part = jgarriss Domain = mitre.org DFDL is capable of parsing and validating these as three elements. No problem. But let's suppose that I don't want one of these elements, the display name, to make it into the infoset. I just want to drop it on the floor after I parse it. Question #1: Can I do that? If so, how? Alternatively, suppose I want it in the infoset, but then I want to programmatically remove it from the infoset *before* I unparse it. Question #2: Is that possible? If so, how? TIA