[Raynor]

Originally Posted by Boro

So, he has to conceal his power as he had done when he found Grima.

His power at that time, as it has been noted several times in this thread, last time by CSteefel, is mainly fear. That power, as The hunt for the ring, UT, informs us, cannot be in fact concealed, being the major drawback of using the nazgul. What still remains unaddressed is that the WK use of magic during the times he encountered Frodo is far inferior to the Pelennor Fields. It is these times that I have called into question, not when WK met informants or Gandalf. This is when he was closest to his ultimate goal in the mission, but failed to impress by magic, although it would have helped him a lot. The fact of the matter remains that, instead of confronting his enemies - as his power you attribute him at that time warranted -, he rather bids his time, waits for the morgul blade to take effect, flees from Aragorn and all that.

'There, put in command by Sauron, he is given an added demonic force.'

and

'There, put in command by Sauron, he is given added demonic force.'

The first one says the Witch-King, because of his command given by Sauron has an added demonic force (I take 'demonic force' to mean that he's scarier...as the entire part is about the fear the Witch-King inspires).

The second one says that because the Witch-King, because he was put in command by Sauron, he is given added power (that power being 'demonic force.')

Then again, the main differences between these phrasings is not the presence or absence of "an" [I fail to see why each phrasing would exclusively warrant just that one interpretation you gave them] but the meaning of "demonic", which makes this exercise rather useless.

So, clearly the Witch-King must have done some sort of 'gate-busting' sorcery before Pelennor Fields, or he would not have been known to people as being a sorcerer.

Gandalf indulged in far less impressive shows of power and yet he was still known as a wizard.

And the Witch-King, seeing Gandalf was standing in his way completely unafraid, leaves that situation to go tend to another.

It's not because he sees him unafraid that he leaves.