Holding 2 opposite directions at the same time causes you to move right.

So normally if you hold 2 directions you would go diagonal (if you hold a vertical and horizontal button.) If you hold right and left you go... right? if you hold up and down... you go to the right. if you move diagonally and press the opposite direction you are going in nothing happens and you move in the original diagonal direction (prevents the above mentioned glitches.) I think the player's brain is a little broken.