Maybe but that makes sense when this "smart person" leaves then no-one knows how to keep their stuff going and the system is likely to crash and burn taking the

Maybe but that makes sense when this "smart person" leaves then no-one knows how to keep their stuff going and the system is likely to crash and burn taking the manager with it. If you have a 4 person team you can handle people coming in and out over time, using best ideas from the team.