Re: Too much knowledge
Leslie Thomas wrote a novel "The Tropic of Ruislip" (1974). One subplot is the ancient gardener who maintains the golf course greens. The club committee schemes to force him to retire on a pitiful pension.
It then transpires that he is the only person who understands the course drainage system that was installed when he was an apprentice. So - he gets to stay working at a higher wage, with the promise of a good pension. In consideration of his age he gets to work less hours - with an apprentice - while he documents the drainage system "overr the next few years".