I must also agree with OgOggilby I really enjoy the intro to thief as it is. Whoever composed it did a wonderful job. I definitely believe that about them getting someone to compose something similar though. The two pieces are in the same key, and the Thiefopening borrows several small fragments from the Tallis Fantasia. I was convinced they where the same song when I was only listening to 30 sec clips of the Tallis Fantasia until I found out it was written for strings only. But definitely keep the anonymous song.