We Offer a New Razor" - Gillette's first advertisement (System magazine, Nov 1903)
The pattern
This still is filed under If-then promise.
Define
A conditional contract: if you do this, you get that. The sentence can be tested against the reader's own case.
Mechanism
Specificity does the persuading. The if names the action. The then names the outcome. Hedging kills it.
Verdict
We can name both the action and the result without adjectives
Why it works
The headline is a plain announcement with no adjectives, which reads as news rather than salesmanship and buys the reader into a long column of specifics. The copy then does mechanism selling: it tells you exactly how thin the steel is by comparing it to the paper you are holding, which converts a spec into something the reader can feel in his hands. The economics are made concrete and tiny, five cents a blade, so the $5.00 entry price gets reframed as two years of shaving. The close inverts risk completely - no money up front, return at the seller's expense, refund on your word - which removes every reason to defer the decision, and the coupon gives that decision somewhere to go.
Steal this when
You are launching a product category that does not exist yet and the reader has no mental slot for it. Lead with the flat announcement, spend the body explaining the mechanism in physical terms the reader can verify, then remove all purchase risk so trial costs nothing but the act of asking.