Mayweather is the most technical fighter in boxing right know but that alone is not enough to be p4p the best. The quality of opposition is the most important thing. His resume the last 5 five years is a joke. Baldomir, Brussels, Gatti, Mitchell, De la hoya, Hatton, blown up Marquez. Mayweather doesn't have the heart or the courage to move up 2 divisions and fight there. Right now I put him at number #9. When he beats a real welterweight then we can talk about he being #1.
Wherever Mosely is, Floyd should be behind Mosely. Same weight division. Floyd has to prove it to be back as #1.