[parasubvert]

Perhaps Canada is just different, there is no discovery for income: the judge orders sharing of your T4 (1040 equivalent) with your ex every year which shows all income, capital gains, dividend gains, etc. By law it's what's required. Child support is usually a formula taken from a rolling average difference of income adjusted by regular access (50/50 parenting vs 70/30). Ability to work at past incomes due to illness, recession, etc. can also adjust this.

From a public policy perspective here, the family justice system is designed to encourage settlement and not go to trial: almost all cases need a dispute resolution or case conference ahead of trial to provide a preview ruling.

What is the policy you would prefer?