First he had to pull his head from it's hiding place.
Riding anyone's wheel on the aero bars, especially a stranger's, is stupid.

There are maybe 1000-1200 riders in the world skilled, experienced, and practiced enough to do that regularly behind a cyclist they do not know or ride with on a very regular basis.

Most of them just got done with their big race....

We have a group here that does that on a regular basis.
They ride aero, wheel to wheel in a pace line.
They wreck all the time.