In SliceAnalysis it is stated that "SceneView.analyses can contain multiple slice analyses, but only one of these analyses can be active at a time".
Applications that use ESRI's ArcGIS Javascript API (like EXB and WAB) with 3D Scenes,
currently do not have Swipe widget (which is currently available only for 2D maps, but not for 3D scenes).
Swipe Widget is crucially important,
for example to compare IntegratedMeshLayer from one year at rightside and from another year at leftside.
By enabling SceneView.analyses to contain concurrently 2 active slice analyses (Slice Planes), there is a solution "out of the box" to mimic the Swipe widget, by activating 2 SicePlanes back-to-back.
(Another solution, maybe more complicated to perform, is to enable the SlicePlane to operate independently on its both sides, so it could display one layer at right and another layer at left.)
