BCGControlBar Pro for MFC
static const CSize& CBCGPDockingControlBar::GetDragSencitivity ( )

Returns the drag sensitivity of a docking control bar.

Overriding this function you can control width and height, in pixels, of a rectangle centered on a drag point to allow for limited movement of the mouse pointer before a drag operation begins. This allows the user to click and release the mouse button easily without unintentionally starting a drag operation.