Bloodvine Set - Tailoring required?

Quick question about Bloodvine Set. Saw today someone mention that the set bonus is what requires tailoring - not the actual pieces of gear. Is this true? As a Shadow Priest crit % is pretty low on the chart. Curious if I’ll be able to wear these pieces without tailoring and just miss out on a stat that means very little in order to keep eng/mining throughout Classics life span.Thanks.