I don't think it's necessarily extremeley calculated, no, but I do think instinctively Ianto knows how to manipulate people. I love your interpretation though, the idea that Jack will reciprocate his feelings, which he doesn't want to have in the first place, and that somehow that will result in Lisa getting fixed and everything being okay, his feelings for Jack and his feelings for Lisa just becoming this big fucked up muddle in his head, that works for me, yeah.

I love groovy comments like this. Yay for thinkies.