Someone added a paragraph to the Wikipedia entry
https://en.wikipedia.org/wiki/North_American_Datum
which was not clear at all. I tried to clean it up, but have a nagging suspicion that it can still be misinterpreted. And there is a small chance I have the directions wrong. Can someone verify or correct this for me?
"NOAA provides a converter between the two systems.[8] The practical impact is that if you use current GPS device set to work in NAD83 or WGS84 to navigate to NAD27 coordinates (as from a topo map) in Seattle, you would be off by about 95 meters (not far enough west), and you'd be about 53 meters off in Miami (not far enough north-northeast), whereas you would be much closer for points near Chicago."
Your estimate for Seattle is good but It's more like 47 m around Miami. I corrected Wikipedia to reflect that value.
Thanks. I should check my entries more carefully, sigh.