Although it may indeed be true for most cases of white EE's, the rest would be hard to judge because most people don't really know how to describe their EE colors to help the correlation.
For example, if someone has a typical silver duckwing EE, they'd call it gray or black and white. . Then another comes along, calls theirs Silver Duckwing with blue, so then that gets categorized elsewhere. . .
Truthfully, I think the most reliable way to tell an EE's egg color is by her comb size and shape. The bigger or taller or floppier the comb, the bigger chance the eggs are green, due to the modification in the normally small and tight pea comb from the crossing of a brown-laying single combed bird. Or, from another green layer with a modified pea comb.
But, for people's enjoyment - I had a Golden Duckwing EE cockerel with dominant white on him, and he had the genes for purely blue. I know this because his offspring crossed with Polish laid perfectly light blue eggs. They matched very well with my Ameraucana eggs.
I also had a BBR Easter Egger hen who laid brown eggs,
however such a case should not be considered, as her comb was a single comb anyway