Halliday & Matthiessen (1999: 170):
[The projected type of Range] is like [the enhancing] type in that in both types the agnate expression takes the form of a circumstantial element (grammatically, a prepositional phrase). But in the projected type the circumstance is one of Matter, whereas in the enhancing type it is typically one of Extent or Location. This corresponds in process type to the distinction between saying and sensing on the one hand and doing and being on the other.