"Yeah, that was definitely on my ordered list... on my list of things to try.  I reciprocate... for your game-theoretic... oh my ass, does this language really not have a less than ten-syllable way just to say 'thank you' - there it is.  'Thank you' for your helpful help, which I do understand to have been offered in a spirit of intended mutual future profit and not just friendship."

"Yeah, that was definitely on my ordered list... on my list of things to try.  I reciprocate... for your game-theoretic... oh my ass, does this language really not have a less than ten-syllable way just to say 'thank you' - there it is.  'Thank you' for your helpful help, which I do understand to have been offered in a spirit of intended mutual future profit and not just friendship."

There's a polite dath ilani thing to say when you're thanking somebody and you're not sure how much of their help was pure altruism or not, but if he tries to say that thing, it'll take eight thousand syllables and then the other person still won't know how to interpret it colloquially.