I think the issue with the debate is that it is coming from two different bases.
Those endorsing str/dex are suggesting that you have already overgeared the content.
Those suggesting vit are considering progession, where you are not overgearing the content.
If we are considering over gearing the content sure, whatever gets you ahead.
If you don't? Vitality is probably going to be best due to helping in the worst case scenario, or fights such as turn 2 where you cannot block/parry any of the attacks.
Also Ciana, I remember that debate, and I believe the reason eHP was considered better, even though a gain of .01% of eHP was small, was because the attacks that could kill you, such as Crucia's breath, could not be avoided/blocked/deflected.
