I guess it's possible. Although I must admit I have some difficulties reconciling this with what we've seen of Jack in TW so far, because there he usually is concerned about the people he loves and their happiness, even when he's only with them for a brief moment, like the original Captain Harkness, whom he wanted to be happy with his girlfriend. He pushes the boundaries occasionally, with Estelle and the promise they made, even with Gwen in S1, but never even remotely as as far as marrying someone under false pretences. But then again, that might be because he learned from painful experience... Obviously there still is a lot of leeway when it comes to Jack's characterisation from the 1860ies to at least the early 20th century.

(I absolutely agree about the procrastinating part, though.)