What is the current state of the law on liability under a promissory note?

I am mindful of the decision of Bennett J. (as she then was) in Gabbs v. Bouwhuis, 2005 BCSC 1782, a case not referred to by either party. In that case Bennett J. allowed amendments that provided alternate grounds for finding liability under a promissory note which the defendant had signed. The original averment alleged that the defendant was the guarantor under the note. The alternate grounds to be pleaded were that the defendant was the maker of the note or in the further alternative, an accommodation party to the note. The amendments were allowed. The amendment allowed were simply alternate theories seeking the same relief based on the same set of primary facts, the signing by the defendant of the note.