Thanks. Sort of (I think) understand that. Just didn't understand the way the camera behaves wrt evaluative and spot, and metering vs focus point.
Don't mix up metering with focus.
Focus points are just that, points where the cam can focus at i.e. either center or any point you/cam chooses.
Metering: cam calculates exposure based on what it sees in the viewfinder.
Evaluative/matrix tries to have a uniform exposure across the entire scene.
Center-weighted gives more weight to the center.
Spot calculates exposure based on a 5-10% area of the scene, usually around the center focus point - though on some cameras the "spot" can be shifted to other focus points.