The Autobiography of 'Sunny Jim'" - Force wheat flakes long-copy ad (Ladies' Home Journal, 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
Writing the ad in the mascot's first person lets four different jobs - origin story, purity argument, rumour rebuttal and coupon offer - sit inside one continuous voice without reading as four separate advertisements. Every proof is dramatised instead of asserted: cleanliness becomes the boy-versus-doctor comparison, scale becomes a hundred thousand packages a day, social proof becomes two million people eating with you that same morning. The layout also teaches the campaign's own history back to the reader, reprinting the hoarding, the strip-cartoon billboards and the first jingle, which flatters the reader into insider status; the cut-corner coupon then converts that goodwill for the price of a two-cent stamp, so a long entertaining read still ends in a measurable response.
Steal this when
Use this when a mascot, founder or character can plausibly narrate how the thing is made and you need long copy to be read voluntarily. It needs an already-famous campaign to refer back to and a low-friction offer at the end to catch the reader the story has warmed.