if there were a guy mayweather jr's size who fought like rigondeaux it would present all sorts of problems for mayweather jr at this point in his career, and he would have great difficulty being able to get off with his offense. mayweather jr would need to put together punches at some point in the fight and win by knock out because he would not be able to win by outboxing the guy. a younger mayweather jr vs the current version of rigondeaux would be more interesting.
If you're going to do lb for lb, then you have to assume both fighters are at their absolute peaks as well. Rigondeaux is still at his peak, Floyd is clearly past his. I think the 130 lb Floyd beats Rigo by close but clear decision.
The Million Dollar Question is, WHO LEADS???...Also, WHAT Happens If/When Rigondeaux Catches Floyd FLUSH???...Lb for Lb, REED Thinks Rigondeaux TAKES Floyd's Shots BETTER than Floyd Takes His...Doesn't Mean he BEATS Floyd Though...Floyd's Superior DEFENSIVELY, but Rigondeaux's the HARDER Puncher...