The fact that the teleporting gravity manipulator is faster and more agile than him, I would say.
Speed equalized not how it works. His movement is equal to hers, regardless of her special abilities, they move from Point A to Point B at the same speed, if she decides to **** off hundreds of meters away, he's gonna have a few hundred meter head start to lose her or go to where he needs to go. And if speed wasn't equalized, he'd blitz her to hell and back, she isn't faster in this situation, she's on par, and that's to her benefit.
And teleporting? Kinda has to know where he to teleport to him no? In fact, he might be able to use that in his favor. Then again, has she ever used her teleportation in combat before?
Well, PIS is out during fights, so unless you can suggest an actual strategy that he could think up given the information he has, is able to physically perform and would work on Kat, it really isn't an argument.
It isn't PIS lad, it's a integral part of his character, just because we don't get an explanation every time doesn't mean it didn't happen or he can't do it again, that's his whole schtick, sleight of hand to a bullshit degree.
As it stands I'm just gonna counter argue that all of that is, in practice, physically impossible for him to pull of against Kat mid fight.
Unless he does it, not gonna ignore a character's whole schtick, what do you want me from me? To outline a super 400IQ plan that'd he pull off? Kind hard, I ain't 400IQ, all I can say is based on past precedence, he'd probably kill her with a piece of a string or a glass of water, **** if I know. Maybe lure her to a place of his choosing, inside a building filled with hamon infused wire traps that she wouldn't readily notice, she makes contact with one and bam dead, or make use of his equipment like a tommy gun and pump the bullets full of hamon. Or just pretend to die and take her out later on. hell even just ricocheting hamon infused items into her blindspot would be deadly.
Also half of that isn't even impossible, what's so hard to believe that the dude can set up a wire trap mid fight, or playing dead? He's done both before against opponents that would **** him up well beyond what Kat could and Kat ain't omniscient, she won't know if he's dead for real or not, and given Joseph can go as far to halt his breathing and heart rate for a good length of time, wouldn't be hard to fool.
I'd also like to point "There is a time limit for Kat's ability to fly." straight from her weakness, I'm aware that people in this thread have said otherwise but given every time is prefaced with "maybe", "probably", etc, I'm gonna need actual evidence for this because it sounds like not even you know for sure.