The rag joint is there to act like a metal universal joint and to dampen out vibration. The extendable shaft is there to let the column collaps in a crash to meet covernment specifications in new cars . Both of those things are ignored a lot in hot rods. there are more compact vibration dampers and some companies are now building after market collapsible colums for street rods. Most hot rods do not meet the govt regs for new cars and that is one of the reasons a lot of politicians oppose any modifications to cars even though a lot of things done improve the older modified cars,, disc brakes better suspensions , better handling and enough power to get out of some problems. and they want to scrap older cars.