The judge preferred the evidence of the Claimant's expert because of the Defendant's expert’s approach to his task as expert, his confusion over the proper approach to what prior art was and was not in the common general knowledge, the number of assertions he made which he was forced to resile from as incorrect, and his failure to acknowledge a key fact.

In considering whether to appoint a scientific advisor or order the exchange of expert evidence, the judge in a patent case considered the dividing line between the two roles.