With VSync enabled (Unity Update matched to a 60Hz monitor) and low processor/graphics loading (no dropped frames) the Time.deltaTime should be a near constant 16.67ms.
However, if you measure Time.deltaTime you will see it varies drastically from 2ms to 30ms causing visual jitter... (with an average of 16.67ms). This issue occurs with a blank new application with a blank scene (Windows 10).
Thread for Discussion (Unity has reproduced the issue)
Issue Report Here