To the editor: The casual reader might interpret Robert Strauss' op-ed essay on James Buchanan as an indictment of the value of legislative experience when evaluating the qualifications of a presidential candidate. For those folks, I would urge them to re-read Strauss' closing statement: "The presidency is a singular job whose best practitioners apparently are just singularly adept people." This attribute is not readily apparent in the GOP nominee. It seems to me to imply that the best presidents have little or, maybe more importantly, no prior government experience. The implication is that our worst presidents have many years of government experience. Yet I think if one looks closely at the list of "best presidents" we see men with backgrounds that very much connect them to government.