Path Nodes.

[palistov]

Don't assign him each path node. Assign only the one you want him to travel to. The AI will select path based on the path nodes you place. If you don't like the path he takes, split it up into segments (every 4th node or so), or you could just adjust the path node placement in your map.

Edit: To clarify, don't DELETE any nodes. You want to have plenty in your map. Just don't assign grunty every single one.