That reminds me a bit of PEAR, which also held that the "level" is so weak that it requires massive samples to detect. If I recall, in The Demon-Haunted World Sagan mentioned it as one of the three "psychic phenomenon" concepts he thought that it was worth examining further, not because he believed in them, but because the usual mechanisms of science had not yet completely removed all of the confounding factors to reduce the results to mere noise.