In this case, a "mode" is a fixed mix of the pickups. Each mode has it's own loading tone circuit, including a load capacitor, and different tone capacitor values. And there's a master volume control, which is wired the right way - not backwards like on a J bass, so that it turns down the volume, without changing the sound. There are a lot more usable sounds in that bass (at least for how I play) than in a regular VVT wired J bass, and there are sounds you simply can't get out of a standard Jazz. Yes, a Jazz can do other sounds - the parameters that are controllable in my cifrcuits are different from the ones that you have on a standard circuit. The user interface, with a tone control for each mode, allows you to dial up two sounds, and switch between them, literally with the flick of a switch. Or, when you're playing one sound, you can dial the other one to a different sound, without changing the one you're currently using. Also, although the pickups are single coils, there is no way to get a sound that hums with this bass.
A VVT user interface to me, is something where the designer decided "I don't know how people are going to use this...here's some controls, good luck figuring it out". Sure, if you spend enough time with one, you figure out workarounds for the drawbacks of that interface, and maybe you get good at turning 3 knobs to precise locations in a hurry, but to me, this interface is much more usable. I re-wire basses (and the occasional guitar) for people, and one of the things we talk about before I design a circuit for an instrument is how they are going to use it - I don't end upi doing VVT circuits for anyone - if that's what they want, they don't come to me.