It makes a little sense to me that would be the case. People tend to write things they find relevant for their own life or surrounding. That is, he might be putting into paper a kind of warning to himself.
To me it indicates that he knew how easy it is to lose your shirt, likely from the examples of his peers -- and then he did anyways.
But he sounded so clever with his quippy little lines... America loves appearances more than the reality
Americans love making pithy generalized critiques of their own culture based on inconsequential anecdotes.