The C.V. refers to "Constant Velocity" and is referring to the intake manifold, not implying the carb is a C.V. unit. A C.V. carb on a bike can be seen clearly as such by the flat round housing on the top. The throttle cable opens up a butterfly that allows more air to pass through the mouth of the carb and the bladder living in that housing up top actually moves the slide within the carb to regulate actual air/fuel flow based on manifold vacuum. This has nothing to do with this conversation though, just some info.
The reference earlier to the twin carbs not doing anything in the power/exhaust stroke portion is true to a point. You have to remember that each cylinder will only be fed 28mm of air/fuel in a stock setup. The cylinders are 180 degrees apart, meaning only 1 will pull fuel at a given time. When the cylinder fires and blows out the burned fuel, the other cylinder being 180 degrees out will be pulling its air/fuel. This simply means there is 33 or 35mm (They have both available in the kits) of carb feeding both cylinders, only 1 at a time though. This will remain true up to a point where the extra angle of the intake manifold will restrict some of the flow compared to a straighter shot of 2 carbs. This is why people report a marginal loss at the very top end of their RPM range. In short, yes it works. If you'll be duning, MXing, Woods or trail riding, it will be very beneficial and much easier to maintain. If you're drag racing, you'll be better off with a PRECICELY tuned big dual carb setup.