Back on topic has I try to explain my position.
The financial disclosure reports all assets and all income from all sources.
At best, the tax return reports the same income. But when you're involved in 500 plus organizations, it's highly improbable that's the case. It's very unlikely all his income from all sources is reported on his personal tax return. It's more likely that a significant amount of that income is reported by different business entities.
Furthermore, when judging net worth from investment income, you can do that reasonably well with respect to interest and dividends from publicly held companies. Not so well for dividends received from closely held businesses.
More importantly, you can't possibly determine the value of real estate holdings by looking at a tax return. One simple example, you could own undeveloped real estate with a value of tens of millions of dollars that won't be reported anywhere on your tax return. There are many other similar situations.
So to conclude, information found on detailed financial disclosures provide significantly more information than a personal income tax return would.
