I attended this talk on 13 March 2019, and Prof. Gunter DuFey gave me permission to publish it on my webpage.
The most important outcome that I took with me was that it does not make sense at all to speculate in currencies. Exchange rates are erratic. Prof. DuFey: “mit Währungen spekulieren = ein reines Glückspiel! Über längere Zeit 50:50 minus Transaktionskosten und Volatilität.”
The second most important outcome for me is that the main exchange currency of this world is the US-Dollar, for very good reasons.
Here is the talk, (01:09 hours long)
And here are the slides for his talk