The knight can reach the "starting point" shown from it's place in a traditional chess board set-up, so yeah, the knight can go anywhere. The guy probably chose that spot in an effort to use the least number of moves.
I miss chess. I used to play a lot up through middle school. I don't think we had a chess club in high school. It helped that when we were little, my grandmother got my little brother and I a chess set that had the moves for each piece on their respective bases.
So the knight can't go anywhere.