Brian Abraham,
For heaven's sake, don't tell your daughter that
knots are a part of the
Metric system!
As long as the metric system continues to use the 360 degree circle, broken into 60 minutes per degree, and 1 Nautical Mile equals 1 minute of Latitude, the Nautical Mile remains metric!!!!
In the Imperial system, the Nautical mile is a surd, being 6076.11548....... feet to infinity, whereas in the Metric System it remains stuck at 1852 M exactly.
Now, if the metric system were to embrace gradians (the 400 degree circle, an eminently sensible idea), that would be a different matter altogether.
I wonder if the guy who invented knots considered WGS84?
Regards,
Old Smokey