Could this be another way of saying having a plan to consciously use DCA without having to depend solely on discretionary income? I agree with you only when there are other sources of income. For a skilled person whom in most case earn high or someone who can carryout multiple jobs before the end of the month it's much easier to apply DCA without depending on discretionary income because they have constant flow of money.
But a scenario where this opportunities are rare. I mean having the chance to earn more income then the only option is to depend on the available income which in this case fall back to the discretionary income.
You may be trying to prioritize alternative income sources in your statement. I would not hesitate to agree with you on this.
It would be great if you could find alternative income sources and use them in your DCA rather than just doing DCA based on discretionary income. I often notice that we don't talk about alternative income sources much in the investment world. Maybe it's because it's not easy for everyone. Finding a discretionary income source may be somewhat easy for most people, but alternative income sources are not available to everyone and are also difficult to find. But it is certainly possible if we can put in the extra effort.
Having alternative income sources means we don't have to rely solely on discretionary income sources to do DCA. It makes your investment journey easier and helps you reach your goals faster. It even makes it easier for you to plan your finances. Generating additional cash flow and building the necessary funds becomes much easier.