Tosh finally knows. It's funny how obvious something can seem after it's been confirmed for you. Now she can sit and observe them and get all dreamy eyed like the rest of us imagining what the two of them get up to together. Hopefully, while chatting over dinner and sharing Jack and Ianto stories, Owen will get the hint and see how Tosh feels about him. I think rellan has the right idea, too. If they toss Gwen at Hart she's bound to stick. He is a pilot after all.