The Yes Men Strike Again!

The Yes Men spoof on Chevron is one that revisits the common theme of large corporations propagating their “altruistic” intentions in the form of concerned advertisements. What the Yes Men so effectively (and humorously) do is present the campaign in a manner almost identical to the way Chevron did. It's what makes the spoof so effective and the content of the article more attention-grabbing. 

"But what's unique and different here is the honesty. We've never been able to do this before."

With regards to coding and decoding, the Yes Men simply mimicked the original article's method of encoding (and why not, seeing as they already had an effective template for presenting a message laid out in front of them). Since decoding process is mostly subjective to the viewers of the article, the successful transmission of the Yes Men's message relies on the physical interpretation of the article, as well as the content of the text itself (specifically in contrast with the original article). The imitated professional layout and fake emails (all part of the encoding process) make the spoof more convincing (in addition to the already-present charisma held by popular activist groups similar to the Yes Men). 

<Chevron press release> 
<Yes Men press release>