What is the test for cross-examining a plaintiff in a personal injury case?

The questions asked of the plaintiff are similar to the questions considered in Weisberg v. Keibel, [1961] O.W.N. 209 (S.C.). The Senior Master stated in that case as follows: “Notwithstanding that the tendency of the courts has been to widen the avenues of discovery, the nature of the questions which may be properly asked basically relate to the facts upon which the party being examined relies and although a party is entitled to examine the opposite party for the purpose of obtaining admissions, in my view such admissions must arise from facts and not opinions. Accordingly I do not think that a party is entitled to obtain an expert opinion from the opposite party and then use it against him as an admission, for instance in this case to establish a standard of care which the defendant did not follow. If counsel for the defendant asks his client at the trial to express an expert opinion respecting the matters in issue then of course the plaintiff may cross-examine, but I am not satisfied that he is entitled to obtain such expert opinion on an examination for discovery.” (my emphasis)