css3-transitions currently has a bit of prose on transitioning gradients. I'm not sure there's a whole lot of consensus around it; there have been various suggestions on how to improve it, and I'm not aware of implementations (see, e.g., Simon's bug 14612 comment 1 regarding WebKit).
I think we should consider deferring rules for animation of gradients to css4-images.
Maybe css4-images should handle it. I agree that it should be deferred.
Is this a dup of bug 14612?
No; that's proposing we fix the rules for interpolating gradients; this is proposing we remove what's already in the spec.
(In other cases, the discussion on postponing an issue was about a feature request for something not in the spec; this is different because we need to remove something that currently is in the spec, so it's not simply postponing the issue because something needs to be removed.)