The condition that you describe is not common. It is Norm. ( I hate Norm) A little breaker oil may help but the best way is to place an impact on the bolt untill it spins and beat the threaded end in and or do the impact and beat at the same time for the tough ones. No impact you say? Then just a socket with a cheater bar and still hit the threaded bolt end with a BFH. You should place a bolt on the end so that you dont bugger up the threads in the process.
Even in the later way, I have never been beat by those bolts. That is why they say in the books to replace them. Not because you have to, its just that they get buggered up some times in the process