I would imagine the idle speed is based on manifold temperature. Every carbeurated car I've had used a metal tube that ran from the exhaust manifold to the inside of the choke. Within that choke is a tightly wound spring. As the manifold gets hotter, so does the metal tube, then the spring. As the spring gets hotter, it unwinds...opening up the butterfly valve in the carb, making the car run leaner. To bypass that would make the car run like crap upon start-up, possibly stalling the engine. Then you have to start the car AGAIN with no oil pressure, causing more engine wear. The new cars do this electronically, but the end result is the same, I imagine. It would cause more wear to bypass this system, and would no doubt void the warranty. Of course, I could be wrong.