Okay, I'll throw my two cents in here.

From the start (at least since Walkabout) there has been an emphasis in Locke's flashbacks on stategic game playing. At the box factory, he plays a battle strategy game with a co-worker. At the Walmart-type place, he works in the toy section and explains the game of mousetrap as moving about the board, contructing a trap to catch the elusive mouse. When they are packing up the TNT, Locke asks Jack if he liked to play games as a kid. Makes a joke about the game Operation and almost laughs as Jack jumps when he goes, "Bzzzzt!"

At the time, I took it as a metaphor that Jack doesn't like surprises, and Locke loves the idea and enjoys anticipating them.

Now, when Locke tells Ben that Ben and the Others "are cheating" I think that Ben's talk at the end about the ways that Jack and the Sub could have played out seemed as if he was taking the time to explain his actions as though they were the moves to further a game-type strategy. Like, "I can move this way, or this way, or that way. And here's what would happen if I did each of them."

Now...Locke being soaked to the skin is a clue. He either placed the C4 charge on the outer hull of the sub, after he checked out the inside of the submarine (and that sub is too big for one man to operate, which might mean his first idea was to steal it, but since he couldn't, he blew it up)...or he opened the ballast tanks and sunk the sub in place and then rigged the C4 to detonate in the water above the sub to make it seem as though it had been blown up.

Strategic thinking.
Like playing a table-top war game with real people and things.

__________________
charlie98210
"Whoa!" she said. "Cry 'Havoc!' And let loose the dogs of war!"
And, like Banquo's ghost, they just won't go away.