What is the test for establishing a reasonable assumption of jurisdiction in real and substantial connection?

[37] In Hunt, at p. 325 S.C.R., the court held: The exact limits of what constitutes a reasonable assumption of jurisdiction were not defined [in Morguard], and I add that no test can perhaps ever be rigidly applied; no court has ever been able to anticipate all of these. The court also held that the real and substantial connection test “was not meant to be a rigid test, but was simply intended to capture the idea that there must be some limits on the claims to jurisdiction” and that “the assumption of and the discretion not to exercise jurisdiction must ultimately be guided by the requirements of order and fairness, not a mechanical counting of contacts or connections”. This plea for flexibility echoes Dickson J.’s comments in Moran v. Pyle that it would be “unnecessary, and unwise, to have resort to any arbitrary set of rules” for jurisdiction and that an “arbitrary and inflexible” approach is to be avoided.