The diviners in the Dick Smith test were all able to divine the water location in the pipes reliably and repeatably when they could see the water was there, and they all confirmed they could feel/sense/divine the water in its location with their divining skill.
But these diviners were then unable to divine the correct water location once they had find it without being able to see what pipe it was in.
How about alternative tests?
How about a test in an open field, with a number of diviners? It's been done.
"The Dale et al blindfold test took place in Maine during August 1949. A sandy field was carefully chosen where visual cues to the presence of water were absent, where water was present at depths not over 5 metres, and where the ground was soft enough for test pipes to be driven down without drilling....the diviners' estimates of depth and flow were wildly high and even the best showed no relation with reality. Worse, the diviners agreed neither with each other nor with themselves when blindfolded."
Or a comparison between divined locations and undivined locations? Done.
"Between 1918 and 1945 (the last year for which records were kept) the NSW Water Resources Commission was obliged to drill on whatever site the farmer specified. Of 1832 divined sites, 70.4% yielded ample usable water and 14.7% yielded no water. Which may seem like convincing support for divining. But 1858 undivined sites performed even better -- 83.9% yielded ample usable water and only 7.4% yielded no water."
"In the 1950s the farmers in Central Australia demanded that the government employ diviners because geologists were not finding enough water. So the government did. A subsequent check of the records showed that the geologists' success rate was 1 in 3 but the diviners' success rate was only 1 in 12."
How about a simple blind test...that's been done, too
"Let any blindfolded diviner find underground water on any flat site free of obstructions. Then see if the position can be reproduced when the blindfold is removed. Take care to avoid surface cues, onlooker feedback, and markers that can be seen by peeking down the nose. Such tests have been been reported in Victoria and South Australia, New Zealand, and the USA, involving a total of 87 diviners. None performed better than chance."
From: http://www.undeceivingourselves.org/S-divi.htm