Re. Picture of canal in NZ:
In 1989 I was in a Toyota Hi Ace minibus on that road in a 40+ knots side wind (Skiing Trip) My speed sailing mate and I were hanging out the window in amazement
looking for the bits that had just the right angle.
Didn't have a windsurfer with us though!

Three things I remember:
-The wind was
extremely gusty!
-The driver was struggling to keep the van on the road using
both lanes
and full cross arm technique and the girls (OK, us too

) were terrified!
- The following chop build up on the bits that were the right angle was
horrendous!!!