Good cop, bad cop - Is Trump a negotiating genius?

Is Trump a negotiating genius? Or is he just aggressive and erratic? I honestly don't know. But I do know that 'good cop, bad cop' works as a negotiation tactic. I've fallen for it myself and I've also used it on my son to get him to do his homework! Maybe good cop, bad cop, is how Trump gets his 'deal'? 

So what is 'good cop, bad cop'? In the classic Hollywood cliché, the bad cop roughs you up, turns off the camera and threatens to do even more... then all of a sudden, here comes the good cop! He befriends you, tells you he can protect you from the bad cop... if only you can give him something.

Academic research suggests 'good cop, bad cop' works

Academic research suggests 'good cop, bad cop' works. In a series of psychology experiments, people are more likely to submit (take part in a meaningless survey) if they have been roughed up by an emotional shock. They also have lower memory recall and therefore analytical ability when their emotional state has been changed.

(See summary articlehere or full academic paper here. Other experiments written up here.)

This could explain Trump's negotiating strategy...

 This could explain Trump's negotiating strategy:

 You want to buy a property for a million dollars?

- Low ball them with a half-a-million offer first.

You want to make a deal with North Korea?

- Threaten to wipe them off the planet first!

You want China and Europe to open up their markets to US products?

- Threaten to block their exports first?

I honestly don't know if Trump is genuinely erratic and aggressive or a negotiating genius. He appears to have backtracked somewhat on NAFTA, but has not on Iran. All I do know is that we're seeing a lot of bad-cop Trump right now in terms of world trade, but that could be his way of getting a deal.