Letters That Make Good: A Desk Book for Business Men
The pattern
This still is filed under Direct-from-the-founder letter.
Define
A letter in one person's voice, written as if to one reader, signed by the person who owns the outcome.
Mechanism
Personal authority. The signature is the proof. The tone is the brand. A committee cannot write this and keep the mechanism.
Verdict
Trust sits on a person
Why it works
Splitting the book into an anatomy section and a facsimile section lets it work two ways at once - read through as a course, or opened at the index for the one situation on today's desk, which the preface to the third edition says was the whole point of the revision. Reproducing the letters photographically rather than resetting them keeps the letterhead, the typewriter face and the layout in evidence, so the mechanics chapter has something to point at; a reset letter would have silently deleted its own best lesson. The solicitation frame, the best letter I ever used and why, does the sourcing and the proof in one move, since every contributor is staking his own judgement. The editor's keyed notes give the reason a letter worked immediately beside the letter, which turns a specimen collection into a teachable one.
Steal this when
Steal this when you are building a reference product from other people's work: ask practitioners for their single best piece plus the reason it worked, reproduce it exactly as it shipped rather than retyping it, and key a short editor's note to each one. The two-part split - principles first, indexed specimens second - is the right shape whenever the same book has to serve a student and a person in a hurry.