Re: "Parity of parental living situation": If you reverse the roles the dad could complain that his high stress job, required to raise mums standard of living, gives him less time to spend with the kids or affects the quality of the time he spends with the kids - thus negatively affecting "parity of quality of parental care".

https://www.change.org/p/tony-abbott-remove-financial-incentives-for-mums-to-reduce-visitation