Oh, I know threat generation isn't a 1:1 relation to damage output, but it's generally rooted in your basic melee damage output. What the mechanic essentially does is take your potential damage per swing and turn it into threat based on some unknown formula. This means improving your melee damage output will generally improve your threat generation, whether from haste or weapons with better ratios. If he was responding to something else, he should have quoted that and not the dual-wield argument.