Taking into account information from both videos, and personal experiences with no professional insight, it does seem that it is possible for some drivers to experience some troubles with endurance, but like you said, it does seem a tad exaggerated.
With the second vid, I can say out right, I've NEVER seen such incredible speeds at TMS before. I can only imagine the forces involved, but as you can see, it is possible for drivers to tough it out.
Just throwin' 2 pennies into the hat for ya.