How do we know that he doesn't have it? ^ Clones would not be useless, if he incorporated the two he could basically assassinate multiple targets in a matter of seconds, not just one.
People are jumping with he doesn't have Kage Bunshin because they don't want to open that can of worms. One supper fast character in the vs fights is bad enough, now open the possibility of being 2 or maybe even 3 of them. Minato fighting style does not need raw destructive power, it builds up from speed. So adding the ability to have multiple bodies moving that fast would add a twist to many vs threads.
On the other hand although he might had not access to it during NWW3 he surely had access to it after he became Hokage. As Naruto learned it because he stole it from the Hokage's Secret Scrolls. So Minato did have access to it making it so that all info we have points towards the direction he had Shadow Clones.
That doesn't mean he would be able to use them. We have no info on the chakra levels of Minato and using Shadow Clones brings that risk because you are basically deviding you'r chakra evenly among your clones. Maybe Minato didn't have enough Chakra reserves to make good use of this technique. (but that's all speculation)
Finally i'd like to add that i wish that odds weren't pointing towards Minato knowing KB, because his fan don't need another OP combo to cling on and spam the forum with Minato vs threads. But the fact is that it's very likely that Minato knew how to make Kage Bunshins. As for the ability of the clones to use FTG that goes without saying. Naruto's Clones can use any of his techniques just as good as the original does.
