It's a jokey t-shirt that's deadly serious: Eschew Obfuscation.
Here, in case you need to double check: eschew obfuscation.
You know, I get that the joke is that the diction used is, itself, obsfuscates the phrase's meaning. But if you think about it, that's only for stupid people.
Okay "stupid" was a mean word - but really - if we embraced more fully the more elegant corners of our language, would we not employ such a phrase simply because of its succinct efficacy?*
But that's not really my point. The message is the point. Remember this post to which I linked a few days ago? The part about the jerky lawyers with whom you'll have to deal? Those jerks are obfuscators. If you're one of them, seriously, stop being obstreperous.