Try this. Go to Google maps and ask for 'Directions' between Miami, FL and Paris, France. The map will show you driving directions with just on small dip in the ocean, where the only thing you have to do is just to 'swim across the Atlantic Ocean' for around 30 days...
Now, a bit more weird, make the same search but this time ask for directions between Miami and London. Google Maps tell you to cross the ocean, land in France and from France to go to London. C'mon, I am already swimming, shouldn't I land directly in the UK? Why you make me swim more?
But here comes the weirdest part. If you ask for directions between Cuba and Miami, the answer is: 'we could not calculate driving directions between...'
P.S.:Thanks to Scott that gave me the tip about Miami-Paris!