To his colleagues at the National Labor Relations Board, Marion C. Ladwig is a Don Quixote, tilting away at verbal puffery with a deft and exceptionally sharp blue pencil.

A few quick thrusts and a legal decision shrivels from 14 pages to seven. Whack! He clears a path through a thicket of "wheretofores" and "aforementioneds." Zip! A footnote vanishes. Zap! A bloated paragraph of "pursuants," "whereases" and "parties of the second part" collapses.

The awestruck staff of the NLRB considers this the stuff of miracles. To Ladwig, it's a simple matter of economy. Legal "boilerplate," as he calls it, is not only difficult to read, it also costs money.

"They run off 600 to 800 copies of each one of these," he said, holding up the truncated decision.

Pencil sheathed, Ladwig is a tall, affable administrative law judge who has devoted more than 1,500 of his own hours in the past two years to a labor of love: a new NLRB manual of style to replace a document that Ladwig says "was written by clerks mimicking lawyers' talk."

Like "to wit," "hereinafter," "forthwith" and his personal pet peeve, "vis-a-vis."

"I hate the term," he said. "I don't understand it, for one thing."

Ladwig's 119-page, loose-leaf manual is off the presses now, and already is a hot seller by government standards. The Justice Department has ordered 3,100 copies; the Securities and Exchange Commission signed up for 525. Copies are on their way to the Office of Personnel Management, the Defense Department and other known hangouts of federal rule-writers and lawyers.

The prospect of such a wide readership excites Ladwig, who envisions a steady stream of clean, crisp English replacing the gobbledygook that has frustrated readers of legal prose for generations.

Such notions have been entertained in the government before, of course, from the offices of low-level bureaucrats with a penchant for grammar to the high reaches of the Oval Office. President Carter pleaded for plain English. Commerce Secretary Malcolm Baldrige has made it a crusade.

In that eternal battle, Ladwig's style manual might be considered a beachhead. Today the NLRB. Tomorrow, maybe, the Internal Revenue Service.

Ladwig even harbors hopes that it will lead to a standard, simplified method of citing past court decisions, a particularly vexing problem for someone in his line of business.

Until now, the NLRB has used the complex rules of the so-called Blue Book, the Harvard Law Review's system of citation. But the reference books that line Ladwig's bookshelves are filled with a hodgepodge of other citation styles. The Supreme Court does it one way, lower courts another, the legal publishing industry a third.

With his system in place at the NLRB, Ladwig says, "Our next step is to get the circuit court judges to follow suit. And then if we can get the Supreme Court to go along . . . "

Ladwig's manual is the culmination of a battle against legalese that began more than three decades ago, when he was fresh out of law school and getting ready to draft a will for a client. To his dismay, he found his law firm's standard forms all but unintelligible.

So he drafted one of his own for the client. Then he tackled the whole file of will forms, using plain English.

"A senior partner once told me that 'lawyers' talk' adds to the lawyer's mystique, and the fee he can charge," Ladwig said. "I still prefer plain English."

Nevertheless, the plain-English crusade may have to find a new general. Now that the book is in print, Ladwig said, "I plan to continue working as a judge and not as a grammarian. I made my contribution. Now I plan to resume my job."