Sorry for the use of technical jargon. RO is Reverse Osmosis. SC is Spinning Cone. Two competing technologies, more or less. I'm most familar w/ RO as used by Vinovation is Sebastopol. Technilically, it's continuous counterflow reverse osmosis.
When you have a wine that you'd like to knock the alcohol down a bit (or a lot), you send a small amount of it off to Clark Smith (the mind behind) and they put it into this machine that continuously circulates the wine across this slightly permeable membrane. The low molecular weight material (namely, water & alcohol) oozes thru the membrane into the other side. This is then distilled to remove the desired amount of alcohol and the water is then returned to the wine. The wine is then returned to the sender, back blended, and...voila...the net alcohol is reduced. Also effective in removing VA (volatile acidity).
It's pretty commonly used in Calif, even by high end Cab producers. IMHO, it's a fairly innocous technology.
It is also used in Europe, where high alcohol in wines is seldom a problem, on the grape must afore fermentation to remove some water. Especially in weak or rain-besotted vintages.
Of course, most winemakers are loathe to acknowledge their use of RO/SC for image reasons.