Where should `draggable` be set?

I noticed that the static create for NodeViewDesc sets draggable on dom before outer deco is created (effectively nodeDOM). For nodes with contentDOM and no draggable attribute on their node spec, draggable gets managed on the dom (after outer deco wraps it).

Is this intended behavior or a bug? Should draggable always be set on the outer dom, even for nodes without contentDOM and without a draggablespec?