Arewenearlythereyet...I believe you meant to say the "pound" stops here.
The term 'Copilot' can mean the same as 'Co-Captain', if both pilots each have 10-20 years flying multi-turbine "cross-country".
As for the assumption that a high level of piloting/handling skill means that no major mistakes are possible, this is only a comment about what can happen even to those who appear to be among the best, whether with rather limited experience or much more.
Two NASA astronaut trainees died many years ago flying a T-38 (advanced jet trainer) on an ILS approach into St. Louis International Airport (STL). As far as I know, it had an operating localizer and glideslope, but have no idea whether the localizer and glideslope or flight director(s) were operating properly, or whether a reasonable intercept altitude was provided by approach control, or a crappy "slam-dunk", which happens to all of us. Very closely-spaced parallel runways present various traps to those unfamiliar or in a hurry.
The fact that the tragedy involved two astronaut trainees should be something that we never forget-even after many years of flying much more stable transport aircraft.
A highly-experienced airline Line Check Airman (who gave final "sign-off" at end of IOE for new transport category jet Captains and FOs), with about 12,000 hours, almost scraped a wingtip near equipment beside a taxiway, at night, while he operated on a normal trip. He told me about it. He also admitted to getting a bit ahead of himself, at least once, tuning in the wrong VOR frequency.
So the very best pilots with the best situational awareness and handling skills can not make an expensive mistake? Do they always have absolutely perfect judgement in every situation?
As for widebodies....no, not various Seattle-based Flight Attendants... this might be incidental, but you might find the website (don't know the name) about the MD-11's documented anomalies and aft cg interesting.
All mistakes on those clearly must involve inferior pilot handling and decision-making.
Yeah, right.