Lock was wet. I didnt need to rewatch it. I actually just commented on the last thread about this and here is the topic on it.

he is soaked. He had the backpack with him right? well maybe he hid something in the bag under the dock. he definitely got into the water.

one person couldnt send the sub off and think he could sucessfully retrieve it. if it were sitting on the bottom of the water, then it would not be possible to get into it without flooding it.

i would love to be proven wrong here... but i am thnking the sub is gone and locke is calling the henrys bluff.