Response to object request

Does ECS determine which node responds to a read request based on node performance?

I realize there are multiple scenarios, but I'm going to assume an erasure coded object. If a read request comes in, can ECS determine which node responds to the read request based purely on performance utilization? Can it have node 3 respond instead of node 1 based on node 1's high utilization?

Taking this one step farther, if a read request comes in to site 1's ECS, and it's experiencing high utilization, can another VDC respond to the request?