It takes 4 swings. As long as your Methodical Appraisal, without Discerning Eye, is getting 115, you've got gear good enough to get a 530.

You will need, among those 4 swings, two Discerning Eye buffs and two Utmost Caution buffs. You can pair them up (Discerning Eye, Utmost Caution, Methodical Appraisal, Discerning Eye, Utmost Caution, Methodical Appraisal, Methodical Appraisal, Methodical Appraisal) or spread them out a bit more, as Sartori did.