Hmm, so is this removing part of the feature?  The original user story explicitly required that there be no hover delay when mousing between adjacent hover-preview hotspots (e.g. the vertical stack of colors in brackets_colors.less).  Are there actually any cases where `popoverState.visible` is true (the only time `showImmediately` would be true) but `queryPreviewProviders()` hadn't been called yet?