Can you get in the zone with people watching and judging you intently? If you can't get into the zone with only a couple of people watching you, how will you get into the zone when the whole company is depending on your bug fix?
The pressure of judgement is not the same as the work pressure of a stressful scenario. It's why public speaking and job interviews are among the most feared activities people go through, but people consider meetings boring and mundane.
Easy, the company that is depending on me is not physically there, watching and judging me. Sure they probably are watching and judging me, but as long they're not physically present that makes all the difference to my mind...
The pressure of judgement is not the same as the work pressure of a stressful scenario. It's why public speaking and job interviews are among the most feared activities people go through, but people consider meetings boring and mundane.