there can be 4 procs per 1 swing technically, innate weapon proc, slot 1 aug, slot 2 aug, spell proc (like sk line)... this means you could technically proc 8 times holding a 1h sword and landing a double attack. there's no worry about a proc overlapping or any type of PPM stuff.
however during RoRZ/BL the logic is different, its just 1 proc per weapon (either innate, or your aug) per combat round (so thats 2 procs with dual wield)... or if you're using a 2h it will proc the innate and aug.