Dynamic throttling based on target system CPU load

Let's suppose I had a page on each server that could indicate if it was "too busy". And I used an external monitor or sideband connection to read that page, and indicate if the node is too busy. Now, after a point (especially when we're talking about unexpected load), all the nodes will indicate they are too busy. i understand normally health monitor does not change load balancing ratio (except dynamic ratio load balancing). it marks pool member up or down.