Bendo was supposed to kick Edgar all night, he managed it for the first round and despite being successful, Frankies pressure and boxing forced him away from that strategy. Bendo said it himself.
Diaz is the perfect fighter to exploit that better than Edgar did.
With respect, Diaz's boxing, while very effective, is miles away from Edgar's boxing in terms of styles and how they're implemented in the octagon.
In addition, IMO Diaz is slower than Edgar.