An article way back when in MAN discussed using 'offset' tabs to assist servos on the control surface. In case my technojargon is incorrect, The tab moves opposite of the intended direction of the surface. E.g., if the elevator goes up, the tab goes down. Then there is what is referred to as a 'boost' tab, which would go 'up' further than the 'up' elevator-or down as the case may be. Is either effective, and what factors determine which one is used? Building a Storch which has aileron tabs, but I don't know which type was on the original. Actually made a mock up from pics, but they don't show the whole surface sufficient to tell how it worked. This pic operates like an 'offset' tab, but I don't know which way the full size worked.