This meme was designed by Archie Ransom to discourage people from taking letters to the editor in newspapers seriously. It includes deployment strategies such as: some snide remarks about "shut-ins writing letters to San Francisco newspapers" into a talk show's monologue, and arranging a subplot on a cop show about a deluded kook writing letters to the editor.
The message being: People who write to newspapers aren't serious political thinkers OR dangerous radicals, they're harmless kooks and cranks. Views outside the mainstream are silly and pointless!
The audience is the American television-watching public. The meme was designed to be an endemic inoculation against behavior, meant to inculcate the above Quirk.
The meme was initially designed with a Power of 7, but a critical failure on Archie's Merchant roll (he's been out of the business too long and is rusty!) led to its Power decreasing to a 5. Dr. Frank Stanton at CBS was only able to get the meme inserted on short notice onto two failing programs: The Vin Scully Show out of LA, a mid-season replacement talk show on the verge of cancelation, and into one of the final scripts of the soon-to-be-canceled Mission: Impossible. It was released on February 14, 1973 and began infecting the American TV-watching public on that day.
(I did some quick back-of-the-envelope math on the Power of this meme and its delivery method and a rough estimate of the people affected by the meme who develop the "inoculation" against paying heed to crank letters is something around:
Ratings for bottom-tier Mission Impossible Season 7 episodes: 14.3/22 (!!!). That comes out to roughly 14.3 x 65 million TV households = 9.3 million TVs tuned in, multiply that by 2 to take into consideration families, let's say 18.6 million Americans saw the episode. Given the meme's Power of 5 and the average American Will of 10, that means only people who roll a 5 or less will save vs. the meme. So roughly 95% of the viewers will have this idea stuck in their heads: 17.7 million people. If we take into account water cooler talk about the episode spreading the meme a bit more (say a Will roll at full strength which will affect only half of about the 5% of the people who might hear about the episode personally from someone else: after all, there are no discussion boards or Television Without Pity to amplify the message) and figure another 400,000 people or so will catch the meme second-hand. Seems like a number of about 18 million of America's population of 211 million in 1973 will now have this idea stuck in their heads. And that's not counting syndicated re-runs in the years to come!)