Miami's municipal-bond rating is improving. Mayor Joe Carollo will serve out his term in office. An eerie calm permeates the city's tumultuous political environment. Don't thank government leaders. Thank Miami attorney Ben Kuehne. His courtroom argument was simple: A proposed charter referendum for a "strong mayor" amounted to an illegal recall of Mayor Carollo. That was all Judge Fredricka Smith and the Third District Court of Appeal needed to knock the referendum off this November's ballot. Kuehne's pro bono work allows the mayor to complete his term, and earns for his firm, Sale and Kuehne, invaluable publicity. (What? You say he did this solely on principle?) The political stability should last until Carollo's next outburst at city hall.