OK D.T. I think you're trolling but I'll bite.
This scenario would not be in any policy document specifically. Its a combination of security and income policy and open to interpretation. I have outlined what is needed for this scenario to be considered by any reasonable lender with their own policy discretions.
I am not that big a user of Westpac so I wouldn't be confident which way they would go with it. It wasn't that long ago they wouldn't approve anything even slightly unusual. On the other hand there are other lenders that I use a lot who I know would be OK with it.
As to black and white policy I'd back myself against 99% of my colleagues.