What is the test for a defendant to be held blameless in a motor vehicle accident?

I considered this section in Meyer v. Neuman, [2004] A.J. No. 347, 2004 ABQB 232, and at paragraphs 97 to 101, I concluded that the section creates a presumption which may be rebutted by the defendant. It is the defendant’s conduct that is under scrutiny. However, the presumption may be rebutted if a consideration of all the evidence demonstrates that the plaintiff, by his conduct, contributed in a material way to the accident, and the defendant could not have avoided it by exercise of reasonable care. The defendant does not have to prove himself to be blameless on a civil standard, only that he did not entirely cause the loss or damage. The assessment is to be based on the entire evidence, not by an examination of the evidence piecemeal, nor by assessing the plaintiff’s conduct first.