In what circumstances will an application be allowed to amend the Rules of Civil Procedure?

In Simrod v. Cooper et al., [1952] O.W.N. 720, at p. 721, the following rules respecting amendments were set out: 1. An amendment should be allowed unless it will cause injustice to the other side which cannot be compensa ted for by costs ... 2. The material filed in support of the application must indicate that the proposed amendment presents an issue worthy of trial and prima facie meritorious ... 3. No amendment should be allowed which if originally pleaded would have been struck out as embarrassing 4. The proposed amendment must con tain sufficient particulars to enable the other side to answer ...

The second rule has been qualified in subsequent authorities to make it clear that the court should look only at whether there •is a prima facie meritorious case set forth in the pleadings - it is not to concern itself with the credibility of the plea sought to be put forth by the amendment. See Seaway Trust v. Markle, 25 C.P.C.(2d) 64.