User blog comment:Ghmorello/Chapter 913: The Straw That Broke The Tea Maker's Back/@comment-31434191-20180803065617

Pretty sure he can hold more then 10 dolls if he wanted to, just he has 10 on average. I mean, back against Kizaru he said it is troublesome to fight with a "mere" 10, indicating he can hold more.

But yeah, his power is awesome. Hopefully he stays as an antagonist, much more entertaining that way (plus redoing Capone would be kind of lazy on Oda's part).