"I do, and like I said. There's no tide here. No current. The water is perfectly still, and I'm standing next to you. So, if you're going to try anywhere this is the safest you can possibly get."

He lofts a eyebrow at him, doesn't try to encourage him any deeper or let go. It's Ianto's choice in the end, after all. If he really doesn't want to that's fine too. They can finish up and get something to eat instead.