If we're going to restrict how many enclosures and/or images an entry can have, we should build that kind of information into the @rel registry, and it might be good, if possible, to come up with some kind of policy or guideline for how to determine whether such a restriction will be applied to future @rel values. Given (what I suspect would be) the difficulty of coming up with such a policy, I'd prefer not to have any such restrictions. And if we do decide to have such restrictions for images and enclosures, then perhaps <link> isn't the right way to point to these resources.
BTW, is PaceLinkPurpose completely dead or is it still gasping for life while waiting for language to be written[1] that consensus can be built on? If the dream is not dead, then I don't think <link> is the right place for images, and perhaps not for enclosures either, though I wouldn't argue strenuously against that.
Antone
[1] http://www.imc.org/atom-syntax/mail-archive/msg11631.html
