I could easily be wrong, but I would not have thought that the texture preventing movement would be the reason for doing this. Given the way a properly produced rod is indexed by the bolt. This is why you can't just stick a new bolt in a rod without remachining considerations.

This could certainly part of the reason.

Have a great day,

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Larry Bible
'01 C Class, Six Speed
'84 Euro 240D, manual, 533K miles
'88 300E 5 Speed
'81 300D Daughter's Car
Over 800,000 miles in
Mercedes automobiles