“The World's Strongest Coffee.”
A superlative claim with no number reads as marketing bravado. Buyers want to know how much stronger, and by what measure.
“Add proof: "2x the caffeine of an average cup — lab-tested. Smooth, never bitter."”
Quantifies the strength claim (2x, lab-tested) and pre-empts the bitterness objection in the same line, turning bravado into evidence.