Condition Lever to high idle has nothing to do with the generator shaft, (which never break, by the way.) The objective is to turn the generato faster, so you can get more amps out of it. PT6A-67D required 65% N1 for generator loads below 50% (150 Amps.) To use 100% (300 Amps) required a minimum N1 of 72%.
Some models of the KA200 do not have cross-start current limiters. Their absence allows massive amperage to be pulled on the operating generator and dumped into the cranking starter. To avoid this one can bring the running engine's generator on after the starting engine is rotating well and the starter's draw has decreased significantly.