1. Someone search for keyword.
2. Your site is one of the results.
3. You get the click.
4. User stays on the website enough time and enough pages (this is relative).
5. He closes the window after some kind of engage (also relative) and don't return to results or make another search with this or similar term.
6. In the eyes of Google - the user got quality results and fulfills his intentions.
7. If we say that Google is trying to display quality results - your website is one of them - "people" just love it

8. Make it enough times with really complex strategy (watch out for this, because there are excessive amount of vectors which they will use to catch you cheating - you are mentioning just some of them) and your website will be "the quality result".
9. What Google do with quality results - rank them on top of the SERP.
The Machines will always follow the humans until the real AI

Think about relevant links we use today for SEO - they are like testimonials from other people for something you need. The whole algoritm of G is following the principles of human society.
Just to mention that the browsers are just some of the problem with leak of information about user's behavior.
p.s. Excuse my English - it's not my native language.