The o rings flatten as a result of compression set, this has nothing to do with abrasion.
Abraded O rings display striation marks, ones suffering compression set have simply lost the ability to seal due to a degrading of the elastomer compound.
The same O rings are used in the K16 thermostat which is bolted rigidly to the block, and these suffer the same fate without any aspect of movement other than thermal expansion.
Empirical evidence based upon one car does not constitute an answer to the problem of KV6 owners, and the theory of movement has already been debunked by another KV6 owner who followed to the letter the advice regarding the positioning of the clips on the straight pipe.
Simply put, you can take your pick as to which theory is right, it's been covered in great detail in past threads on the subject.
Brian
