From Ray Monk's 'How To Read Wittgenstein' - no, I haven't - discussing the later Wittgenstein's abandonment of the idea of "a single 'logical form' shared by thought, language and the world, which a philosopher might uncover and reveal":
During his first six months back in Cambridge in 1929... [Wittgenstein] fairly quickly came to the conclusion that the very notion of logical form had to be abandoned. In this, he was helped by conversations with Ramsey and, still more, by conversations with the Italian economist Piero Sraffa. In the preface to Philosophical Investigations that he wrote in 1945, Wittgenstein says that he is indebted to Sraffa for 'the most consequential ideas of this book'... Wittgenstein, soon after his return to Cambridge, was explaining his ideas to Sraffa and insisting - as he had insisted in Tractatus - that a proposition and that which it describes must have the same 'logical form'. To this, Sraffa made a Neapolitan gesture of brushing his chin with his fingertips, asking: 'What is the logical form of that?'
I'd describe the relevant gesture as more of a flick than a brush, but still; attention to life as it is lived, and in a wholly appropriate medium. In other news, I handed in two copies of my D.Phil to be sent off to examiners this afternoon; let us not ask about its logical form.