Just to add my two pence - most of the footage was filmed in + 25 knots, it looks pretty sedate out there on the film but i can tell you it was far from that, the racing was close in to the estuary and the breeze offshore and as for "too close for comfort" Geoff driving the Rib wwas fantastic, he really seemed to know where to put the boat at the right times to get great footage but without risk to crews or boats - BTW shameless plug for my new blog here -
http://catguruuk.blogspot.com/