What is the test for a successful defendant to claim costs directly from the unsuccessful defendant?

In Dhingra v. Pham, 2004 ABQB 973 at para. 15, Veit J. summarized the three part test articulated in other decisions to determine whether a successful defendant should be entitled to claim its costs directly from an unsuccessful defendant: (a) Was it reasonable for the plaintiff to join the successful defendants, given the circumstances; (b) Is there any good reason to deprive the successful defendants of costs; and (c) Were the unsuccessful defendants, vis a vis the successful defendants, wholly responsible for the action.