What is the test for a motion to strike out part of a statement of claim?

The answer to that is found at page 541 of the Fullowka decision, which reads as follows: A motion to strike out part of a statement of claim involves a different danger. Focussing on one defendant and the pleas against him obscures the fact that there are other defendants and other pleas. That is especially so here, where there are a large number of defendants and the amended statement of claim is very long. A claim against one defendant may sound debatable, even dubious. But sometimes it is clear, or probable, that someone is liable, and the real issue is which defendant. If all those persons are sued in the alternative, then the statement of claim may disclose a very good cause of action, though it may be unclear which of them acted, or was at fault. Such a claim should not be struck out: Alexander v. Pacific Trans-Ocean, supra, at 27.