Senator Evan Bayh, an Indiana Democrat and a longtime aspirant to the White House, announced last week that he will not be seeking re-election, thus depriving the nation of his particular genius.  In a column that appears in this morning’s Times, Mr. Bayh gives us an example of what we’ll be missing when he leaves the Senate at the end of this session. In it, Mr. Bayh argues that the federal government would run more smoothly if all 100 senators, Republicans and Democrats alike, scheduled “a monthly lunch.”