I am by no means a thermodynamics expert, but I would think that running the pump faster moving the same amount of fluid through a fixed volume system would be counter intuitive. Slower moving fluid would allow more cooling time in both the intercooler and heat exchanger. Now if you increased capacity of all three, I could see some benefit.
I think that increasing coolant flow rate should reduce temperatures. If slower moving coolant was more effective, than these cars wouldn't need a pump and could rely on convection to move coolant through the loop.