but if you add yourself to +*to and send an email by adding http://test.dwagn.org/wagn/foo+flexmail_test (replace foo with something unique, submit to create the card, then create the linked-to card) you'll see in the email you get the URLs don't work because they're relative.
yes, but let's chew on the name a little. It's specifically about rendering html for email messages. Most of the other fields will use the standard TextRenderer. On the other hand, perhaps not all email messages will be html. I'm leaning towards EmailHtmlRenderer. Thoughts?