User blog comment:Fliu/Chapter 935: Disaster at Udon/@comment-7614831-20190308070627/@comment-28995593-20190308093737

I agree with random guy. Until this point I didn't know that the Seastone cuffs could affect Haki using. So it has to be Luffy being weakend by the Seastone so he can't use his Haki. As for non-Devil Fruit users using Haki while wearing cuffs its no really a question. Esppecially since I don't think anyone would put non-Devil Fruit users into Seastone cuffs. That would be wasting.