Hmm, personally disagree. I think I feel chemistry from them, but it's not the kind you typically see in manga/fiction/etc. It's more of a stable, "we've known each other for a billion years platonically but now it's growing into something more." It's a more like the long-lasting warmth of a banked fire than exploding fireworks, if you know what I mean? I found it fun to see how their view of each other changed and how they're fumbling through their first relationship with each other, and how their long history affects this. So, I can see where you're coming from, but I'd argue that chemistry IS indeed there--it's just in a different form than what's typically seen :)
It's so weird but I don't feel any sparks between them. No chemistry.