I understand why you think that, because there is a strong correlation and it is largely true, but there is more to it than simply being tip heavy. What it boils down to is having mass towards the ends of the knife to maximize its moment of inertia which is the ability to resist changes in rotation. To visualize what I'm trying to describe: a knife being used as a chopper is being swung until it impacts and then (unless the point of impact was at the COP) the blade begins to rotate and this rotation often represents lost energy, or impact energy that isn't going into the cut, and weight at the ends of the piece reduce this. I don't know if what I'm saying is understandable, but it is true and one counter intuitive effect of it is a weighted pommel increases chopping performance in much the same way as a weightier tip, because the mass on the ends of a blade help it resist changes in rotation which prevents the cut from being deflected. So a knife with a neutral balance, but weight towards its ends, can still be an effective chopper. I'm going into this because I want to dispel the myth that a knife has to be tip heavy to be an effective chopper. It tends to be true, but it's not a rule.
So, to maximize the effective chopping power of a knife of a given length and weight you want to distribute the weight towards the ends if possible. This is one reason why bolos and kukri are shaped the way they are. As knife designers Lorien and I have to look at ways to optimize a knife that is going to see many different uses, but one thing that is clear is that a neutral balance and light weight are nice properties in a knife that are largely at odds with being a chopper, but distributing weight to the ends of the piece helps with that. And one tool we have to distribute weight is a fuller. By going with thicker stock and removing weight from the center of the blade but leaving the tip solid we are essentially distributing weight towards the tip. Similar efforts with the design and skeletonizing of the tang give us some tools to help us distribute weight in a design. Ultimately a design always represents compromises for various uses, but when we're finished with it, it is a deliberately tuned package.