Diaz' cardio is such a myth. He was visibly tired while Condit looked completely fresh at the end of their fight. Diaz was also lumbering around in the 4th and 5th from karate style kicks. 5 rounds of GSP's low kicks would be a much different game. Diaz throws low power volume punches while avoiding any real footwork, it's the easiest style cardio wise ontop of that.
His endurance and cardio is not some absolute fact. GSP has never looked tired and has had a huge amount of 25 minute fights. After fighting gravity for 15 minutes we'll see a TIRED Diaz getting picked apart standing by a guy who actually knows how to use angles and get off the line while attacking.
sig credit to Limba