Maybe it was the first time he ever helmed a ship that had just been completed, and the external inertial dampeners are only used for when a ship is going to be "anchored" for a long time due to construction or repairs?Bah. It was a dumb scene. This guy is a professional pilot and he neglects something so basic?
It sounds like a dumb mistake, but it's pretty easy to No Prize your way out of.
Just what I was thinking - he's a cadet, suddenly thrown in as helmsman on the new ship (can't remember the line, but Sulu is definitely not who Pike is expecting to see) - there's a whole list of things he has to remember to switch on or off, I can believe he'd forget one.