Experienced a couple of map shifts in the Far East due to a lack of DME updating even following a good alignment.
First one was a 4200nm jump, we never actually worked out WTHH, second was smaller, the order of a couple of hundred miles but still significant.
Fortunately, heading, speed and time until we came into range of a VOR / DME worked. Mid-Atlantic or Pacific though, different kettle of fish!!