Who invented Weet-Bix?

Image from Wikipedia. Link below.

It's a classic breakfast food here in Australasia -- but who actually invented it?

The Wikipedia article is a bit of a muddle.

"Sanitarium's wheat biscuits originated in the form of a product called Granose which was created as early as the 1900s. In the 1920s a company called Grain Products created a new sweetened biscuit by the name of Weet-Bix. In 1928, Sanitarium acquired Grain Products, which like Sanitarium had ties with the Seventh-day Adventist Church and made Weet-Bix a Sanitarium product."

and ...

"Weet-Bix was invented by Bennison Osborne in NSW, Australia in the mid 1920s. Benn set out to make a product more palatable than "Granose."

So, while something called Granose has been around for a hundred years, and a Christchurch Company named Grain Products created Weet-Bix in the 1920s (later taken over by Sanitarium -- Australian Bennison Osborne has the credit for inventing Weet-Bix in the mid-1920s? Something here doesn't quite sound right.

Neither the Aussie nor the Kiwi sites for Sanitarium mention Osborne in their Weet-Bix history. References to him in Google seem to point either to the Wiki article or just repeat the article verbatim.

What brought all this up? I'd found an article I'd filed ages ago as being from the Auckland Sun, 21 December 1921 (but, chances are high that I put the wrong year in the margin from tiredness. The Sun operated from March 1927-1930 ... so the date is more likely December 1927 or something like that.)

"TASTY BREAKFAST FOOD
WEET-BIX IS MADE IN N.Z.

"For years doctors, school-teachers and business men have been urging us to 'start the day right.' They recognise that the man or the child who has the right kind of breakfast -- is properly nourished, without being too heavy -- will do the best work.

"Two of three years ago the 'Weet-Bix' people attacked this problem and by careful work found out the right way to make wheat -- the most nourishing grain in the world -- as tasty as possible. The result is 'Weet-Bix', which contains nothing but wheat, and New Zealand-grown wheat, too, which is so tasty that everyone in the home will eat and even demand it for breakfast.

"Further 'Weet-Bix' is proved to be an ideal and pleasant food every day of the week. Young and old enjoy and clean their plates with zest. It is nourishing, too, because people last until lunch time without a worry, yet do not jave that heavy, over-eaten feeling.

"Almost every day the 'Weet-Bix' company, which is a New Zealand concern, received quite unsolicited testimonials from people telling how convalescents 'picked up' with Weet-Bix, how children like it in the hot weather, and so on.

"So, widespread is this feeling of satisfaction that the demand for Weet-Bix is growing fast and the company is making plans to double their plant! This fact surely speaks for itself."

So -- who is Bennison Osborne? Any further info on this would be gratefully appreciated, but so far, the documentation points toward a Kiwi Weet-Bix inventor rather than an Aussie one.

Update 24 September 2009: After heaps of comment discussion: the sequel.
Update 6 August 2012 - finally fixed up the error in the Sun ad date.