header wrap? pro's / con's

I think I read somewhere that the melting point of steels are in the range of 2000 to 2200; about double the combustion gas temp as it exits the heads with a proper street tune, at full load full power,lol. Which happens how often again? How about almost never, cuz most of us build engines that spin street tires to well over 65 mph,lol. And the engine ain't a workin' 'til the tires quit a spinnin'.lol