What is the threshold for sustaining a pleading under Rule 21.01?

In Thode v. University of Ottawa, [2012] O.J. No. 6080, McNamara J. determined that the threshold for sustaining a pleading is not a high one. Accordingly, “[m]otions under rule 21.01 will only succeed where it is plain and obvious, assuming the facts plead to be true, that the pleading discloses no reasonable cause of action. The approach must be generous and err on the side of permitting a novel but arguable claim to proceed.”