Without being able to quote the Prime Minister directly, every individual under the act clearly has responsibilities to recuse himself when the decision at hand meets the relevant criteria. It complicates things a little that the act differentiates between family members and relatives, and family members are limited to the nuclear family, so I'm not sure how the commissioner, for example, would interpret this.
You're right to the extent there's no escaping having to make the decision to recuse oneself. That part goes with the role and the terms of the act.