I don't know whether most scientists would subscribe it but my guess is that most theoretical physicists would, and I would, too. A solid structure of science - a solid theory extracted from a lot of repeated experiments that suddenly made sense - is more reliable than a particular observation of a particular individual, no doubt about it. In the context of physical scientists, well, experimenters are often wrong, too. Of course, if they were ideal craftsmen and if they could also perfectly evaluate all the theory that is necessary to interpret the data correctly, they would always be the most perfect source of information. But it's just not the case. Click my name for more comments about the relations between theory, experiments, and confidence.