The whole concept of how a bolted joint works and maintains clamp load is based on 'stretch'. Elastic stretch is a good thing. The amount of bolt/stud stretch is controlled through torque application. A non-elastic bolt with "all the stretch removed" is about the worst idea anyone could have for an automotive joint.
The other point is that everything shrinks and expands with temperature change, not just the bolts/studs. Also the head and the block expand and contract. Some 'experts' here don't seem to comprehend that fact.
The idea that premium fasteners are based on
"They are recommended for racing applications for their ability to not stretch like its competitors or snap." is also bogus. Does ARP actually say that anywhere?
The sign of a good fastener is both its material properties and design, as well as its consistency and repeatability and minimal variation. Not its ability to 'not stretch'.
In the case of 'low quality' fasteners (think Chinese so-called grade 5 at Lowes), they often have material properties which are lower than their required strength and performance, resulting in permanent yield or fracture during installation or service. Permanent set or fracture is not elastic stretch, and that is a bad thing for fasteners.
Pete is 100% correct.
EDIT:
No, they actually stretch 'quite a bit', not 'very very little'. That is what makes them work across a range of temperatures and loads.
http://arp-bolts.com/p/technical.php
