Technically, there's still a protective film on the crank journals and bearings in the turbo. Cold, high RPM starts aren't good, but, that's what generator sets do every time they are excercised..supposedly once a month. I have seen at least 200 engines that have been in service a very long time and geting the proper once a month excersizing and there wasn't really much wrong with the bearings and the turbo was fit for re use at the time of the overhaul. These are started full throttle, making full power at start up. So, I guess once in a while, it's OK if it happens since these start with no load. But, it is a very scary thing to have something go WFO if yo're not expecting it!