In horizontal configuration, with resources displayed down the left side of the control, a large number of resources will cause the control to stop functioning.  In some cases, like ours, we do not have the option to filter the resources by those that have scheduled events, and so infinite scrolling is necessary for the number of resources we need to support. For reference, see the forum post about this here: http://www.telerik.com/forums/virtual-scrolling-for-scheduler-with-many-resources