You mean the guy who needs to understand the island so he can make the best choices, as opposed to the guys who have nothing they need to do?
What makes you think this is the case? Once again you seem to be mistaking the overseer for some sorta leader. The overseer is not the leader. His job is to oversee plebs. The leader is the bureaucrat, which is a faceless nameless none entity that sees all that happens.
You mean that he can give good orders without knowing the island; someone who oversees plebs isn't a leader; and the term "overseer" is never used for a leading position?
Your interpretation is possible, but I doubt it. Let's hear ebbor's thoughts on the subject...
Overseer literally means:
1.One who keeps watch over and directs the work of others, especially laborers
On this forum, the term overseer often means the unspecified leader of a dwarven settlement. Literal meanings don't mean much; hippopotamus means something like "river horse," and how much does it resemble a horse? Also, hippos aren't restricted to rivers.
But if you say that's all the overseer does...send whoever IS the leader along on the exploration trip, instead.