[black knight]

It's not that it's a mistake...your swing itself is probably very rare. Think about mechanics: the club is only straight to the ball for MAYBE a foot which means that there's most likely going to be some sort of sidespin imparted on the ball, creating a slight fade or draw. For wedges it's less obvious because so much backspin gets imparted to override any (or most) sidespin. It's entirely possible for a swing to routinely hit the ball dead straight, but that's a VERY rare thing. Such swings are rare, mechanically speaking.