TOI, you mentioned the separation of departments as a response to suggestions that Google (as a whole) is making sure the SERPs, ads and all, serve their bottom line. Or maybe you didn't mean it as a response, and it just read that way on the page. Sorry if I misunderstood - just wanted to see what page we're all on.
Google MUST be looking at the end result SERPs to make sure it works for them... beyond that are all those things we can't know for sure:
--What manipulations would boost profits for Google. We can speculate, and some things seem obvious, but as this thread shows there's often two reasonable ways to interpret the same data.
--Which manipulations, if any, Google is willing to engage in from a corporate culture/ethics/legal risk standpoint. That's where opinions are sharply divided because it's a moral assessment of people none of us (?) knows personally.
--Who at Google knows about any manipulations they may be engaging in - or evaluating and then deciding not to engage in.
My own opinion is simply that Google probably considers ANY strategy that might boost profits, and then rejects some which are deemed too risky or too unethical. Where they set their ethics lines, I have no idea. And as for legal risks, I'm not even sure anyone knows precisely what's legal or what's Google's responsibility in a lot of situations. The law is still so far behind on it all.