Being that there aren't many people with this ability, and that there are absolutely no indicators as to their performance apart from letting them do the job ov

Being that there aren't many people with this ability, and that there are absolutely no indicators as to their performance apart from letting them do the job over a prolonged period (as many companies hiring hotshots discovered), and that the position is directly responsible for billions in revenue - I'd say that it's not realistic to expect a drop in replacement.