Shroud will help when its putt putting along and stuck in traffic.
When the temps just climb a little and stabalize under those conditions, that's the shroud helping.
Beleive me, not much fun turning the heater fan on to keep the coolant temps from climbing over the limit... Keep shifting int o neutral to keep the fan speed up, sweating from the heat and sweating from worrying about overheating. Been there, done that, more than once.