Galaxy s5 ART & Dalvik

[gotohealth]

A couple of months ago, I switched my Galaxy S5 to ART from Dalvik. I switched back because of lag and incompatibility issues. However, today I changed it back to ART and I didn't experience the "Android is upgrading" message, followed by all of my apps being upgraded one at a time. Did ART fail? Or could it be because I am rooted and it doesn't support rooted devices?