Bobby Shatford: Last night was worth it. There's nothin like sleepin' with you... just sleepin'... lyin next to you... all warm and sweet... Me wishin' the mornin' would never come.
Moss: What in Jupiter's Balls?
Dale 'Murph' Murphy: So, I guess you're the big hero, huh?
David 'Sully' Sullivan: You would have done the same for me. Isn't that what I'm supposed to say?
Dale 'Murph' Murphy: You can say what you want, but... I'm sure glad you know how to swim.
David 'Sully' Sullivan: Well, that's real big of you, Murph.
Dale 'Murph' Murphy: It's all I can manage right now. I'll work on it. All right?
Answer: Not a ship captain, but will take a shot. If a massive wave is close to cresting, as I seem to recall in this scene, the boat would have to climb a near vertical wall of water and would likely be flipped back and upside down by the advancing wave. Perhaps he was planning to gun the engine to penetrate the wall of the wave, and bob to the surface after it passed. Reversing the engine would just let the thousands of tons of water in the breaking wave smash down on the boat, crushing it.