What is the evidentiary threshold for an order under Rule 7-6(1) to contemplation of an expert's report?

I agree with the conclusion of Mr. Justice Savage in Wright v. Brauer, supra, to the effect that there is an evidentiary threshold to be met before an order under Rule 7-6(1) should be made in contemplation of an expert's report under Rule 11-6(4). That threshold is different from that for ordering an expert's report under Rule 11-6(3). To reach the requisite threshold under Rule 11-6(4) the applicant must establish a basis of necessity for the examination to properly respond to the expert witness whose report is served under subrule (3) by the other party. It is not simply a matter of demonstrating a need to respond to the subject matter of the plaintiff's case.