When making alterations to values of Adjustment Tools, the histogram should update continuously like it does in Bridge/Camera Raw. Currently in Lr, the Histogram only updates after the mouse-click has be let go of; not while dragging the sliders around.
Is something ever going to be done to address this oversight? When adjusting a crop rectangle, the histogram is updated in real-time, as are normal develop adjustments when they are made. I would think that it is more important to have real-time histogram feedback while applying graduated and radial filter adjustments than using the crop tool. As it is, filter adjustments are made by visual feedback, guessing whether the tones in an image are being positioned as required, only to find out if they are when a slider is released. This can't be that difficult - camera raw does it properly! This problem has been outstanding for far too long, please fix this error.