I have been racing since 1974, all but one car mopars. I never have broken a roller clutch, have never blown up a drum either. As you say proper burn out technique will keep the roller clutch in good shape. A broken drive shaft at the wrong time will destroy a roller clutch and no driving technique will stop that from happening. But two of my buddies in one year with just as much experience as me, did blow up their transmissions and it was not pretty, both were hurt, but fortunately not seriously. Both had carbon fiber shields and both got pieces in the car. The drum in a 727 is a bomb waiting to go off, the cost of a good drum is cheap insurance for your car and yourself. I know exactly the science why the drum can and does blow up and have seen the results several times. One night in a hospital will pay for several drums, the cost of a drum is cheaper than a whole transmission case in pieces on the track. Seems common sense to my to buy a good drum. I just figured my luck was no different than my friends.