No, the farther away a flash is from the subject, the harder the light will be. If you put your umbrella really close to a subject, like 3 feet from the person and just out of the camera's view, that will provide a very soft, almost shadowless type of lighting. If you take the same umbrella and move it back to 12 feet, the light will be what is called "harder", meaning it will cast much harder-edged and more-distinct shadows.
Flash power is often called EV, which is a slight misuse of the term EV or Exposure Value, which is a measure of scene brightness that correlates to a specific aperture, shutter speed, and film/sensor ISO setting. "EV" is strictly a way to describe a specific level of scene brightness, so using "EV" with flash is a corruption of the system. It's common among newbies, who also call f/16 a "large aperture" because it has a high numerical value.
"Flash EV" in the new sense of the strobist movement ought to be called flash power,or flash output, and at the actual subject plane, it should be called the flash exposure reading, but so many strobists have no flash meters that they use the WAG or wild-ass-guess method for so many things that they probably have little use for the correct terminology on anything.
And no, an EV value of 1/2 would not be a 0 reading,and full power would not be EV 3--that doesn't make any sense to me. It's a lot easier to simply describe the flash power setting, like Vivitar 285HV set to full, half,quarter, or 1/16th power, or to juts buy a flash meter and describe the flash's output an an actual indicated,measured flash exposure at the subject plane the way it's been done for decades.
If somebody with formal training in lighting tells you the flash exposure value was lowered to deliver an f/5.6 exposure value,that makes a lot of sense and is simple and direct and meaningful, while the fill light was set to deliver an f/4 exposure level, that makes sense. How that is done, either by moving the flash forward or backward, by adjusting the power level, or by zoming the flash head, or a combination of any of those three things doe not really matter,and so using "flash EV" inthe sesne you inquired about is meaningless as a description of how powerful the flash's light is once it finally gets to a subject. But using "flash EV" as a corollary to the flash power output LED or dial on a flash makes no sense, and is fraught with potential misunderstanding. One ought to smply say, I lowered the flash POWER LEVEL to X or to X/X or X/XX. The actual EXPOSURE LEVEL is measured only at the subject plane.
With so many self-taught people in the strobist movement, I've gotten used to hearing people say, "I used a larger aperture, like f/16 instead of f/8, to get a less over-exposed shot."