The resultant 'stress concentrations' between countersinks and counterbores are very different.
But more that than 'simple stress concentration differences'... this could be a very broad topic for technical discussion... believe-it-or-not...
Examples of 'considerations'... just to identify three factors [of many]...
*There are issues with counterbore/countersink depth, radii and hole [and hole-to-fastener shank] 'dimensions', 'alignment', 'tolerances' and 'finish quality'.
*The TYPE of fasteners [or inserts] installed are important, such as: shear-head or tension-head protruding and flush-countersunk... solid or blind... rivets or lock-bolts or screws or sleeves, etc...
*Materials [alloys/tempers] vary in their susceptibility to grain-end exposures failure-modes.
My head hurts.
Regards, Wil Taylor
o Trust - But Verify!
o For those who believe, no proof is required; for those who cannot believe, no proof is possible. [variation, Stuart Chase]
o Unfortunately, in science what You 'believe' is irrelevant. ["Orion", HBA forum]
o Only fools and charlatans know everything and understand everything." -Anton Chekhov
