Obviously it's a highly contested event; it has more registrants than any other event at a typical track and field meet. But I wonder about the talent gap between the 400m and 800m.
The top 400m runners can run 43-low. For them, a 51 feels like a jog. They would only need minimal endurance to run 2 in a row, which would make them faster than the fastest 800m runner in a typical year. And that's not even counting drafting ... which would make the 51 feel more like a 53.
Are you telling me that the top 800m runners wouldn't be quaking in their boots if they heard that Wayde van Niekerk was moving up the 800m?