The legacy of athletes

We talked briefly today about weather or not Brett Favre's legacy was tarnished by playing for the Jets. While I personally think Favre will regain his legandary title from the casual fan over time, it is very debatble. Michael Jordan did a similar thing by trying to play for Washington after his retirement. Roger Clemens left Boston after 13 seasons, was traded from Toranto to New York, and then came out of retirement three times to play for the Astros and came out of retirement AGAIN to play for the Yankees AGAIN. Rickey Henderson was probably the ultimate team jumper. Henderson played for the A's, Yankees, Padres, Blue Jays, Angels, Mets, Mariners, Red Sox, and Dodgers, before ending his career playing in the minors in an independent league. So are any of these players legacies damaged? Does frequently hoping between teams make your career accomplishmnets any less? Or does the play on the field matter more than the uniform an athlete is wearing?