the resistance of the nut on the thread up top is high enough to crack the block as you suggest wouldn't it be enough to cause the stud to tighten up in the block and bind up anyway ? Makes no sense. What is to prevent the stud from turning in the block if its not bottomed out ? furthermore if all one had to do is thread it in by hand then uncrew it half a turn why would they include a hex head in the top ?
fyi i have not seen these instructions anywhere in the arp stud installation directions. harry