Agreement between the tiger and the deer about the tiger's meal, is pure cheating. 
Anyway look... About this particular subject, for obvious reasons, there was a huge effort during the cold war, to find an excuse to justify the stealing. Because it was recognised as stealing to the capitalist world also and as i said and as it is famously well known, this theorem comes with a proof. So, relatively close to the cold war, they ended up with the excuse we have already discussed. The risk of the business owner. That is the best they could come up with and as we saw, this excuse is more than weak. That is what they also teached, otherwise no academic career... Recently, a few years ago, i heard something about trying to justify the stealing through the theory of marginal utility, if you are aware. Of course this failed too and never heard that again since then. The only thing that can really dispute the surplus value theorem is technology, as i have already said, because it might change the situation, depending on the case, making the human work less important.
Anyway, i don't say that you don't know economics, you are probably better than me on many things, why not, but this is not your thing. 
I guess the next subject i would like to discuss with you, if you are in the mood, would come also as a surprise.
By the way, i am not a marxist or something like this...