But it is true, for the temperature to change, a change in pressure MUST occur. This is inherent in a carb because the venturi's (named after the venturi affect) cause a restriction to supply fuel. With no restriction, obviously a motor will make more power ALL else being equal (thats the sticky part and why there's debate, there is no way to insure all else IS equal).

Basically, this guy saying the carb allows lower temps is kinda like me bragging about the 5hp I picked up running my car without oil.