Luffy's gone Gear 4th.....something that's come about 5-10 chapters too late for me to care.
So, Katakuri's just someone who puts up a stoic facade and is actually just a glutton like his mother. Not that much of an original twist at this point, considering the arc has constantly been pulling the twist of characters not being as they first appear (Cracker not appearing in his true body at first, Pudding's split personalities, etc.)
Well, at least the fight's actually started to be more than just filler now.