Not at all. I'm saying if your reason for favoring multiple taxes is to ensure no one dodges all of them, you're barking up the wrong tree. First, this is a dubious goal -- why should the primary objective be to "catch" everybody? Second, if we go by a measure like "percentage of expected tax revenues dodged," a single land value tax would be far preferable to today's messy tax system. (Consider the number of loopholes exploited today and the danger of avoiding a strict land value tax.)
I came up with a scheme that is un-dodgeable (kinda). Print money to pay expenditures, and limit expenditures to keep inflation in check. The tax is implicit, so you can't avoid it. Those holding the currency can't help but give a percentage of the value to the government. It's perfectly flat too.
The only way to get around it is to operate in another currency. But if there are any expenditures at all, they are going to pay someone in the currency, and need to be spent somewhere. This would work best with minimal government expenditures to minimize the motivation to avoid using the currency.
It would be pretty easy to make the implicit tax small enough to not only discourage avoiding the currency, but actually make the currency more stable than others tied to governments that don't know how to control spending.
Inflation is a tax on holding dollars (and fixed income securities). This tax would be pitifully easy to dodge: simply don't hold dollars. This would drive savings rates to zero.
However, it might be temporarily sustainable if a large entity (e.g. China) behaved irrationally and decided to hold dollars in spite of the tax.
If the government is small enough, the rate of inflation would be smaller than other currencies.
If new cash was created only by government expenditures, and not by a lending model like the Fed, I can easily imagine a smaller inflation rate than any other currency. Just limit spending to be a small percentage of the previous year's growth in GDP.
Then people would avoid taxation in other countries and inflation in other currencies by holding this currency.
In a libertarian sea-steading micro-nation, the government would spend money on the police, courts, and prison (though banishment would be a common punishment). The police could be a few prefects who control robots.
There are two problems with this. First, it's not perfectly flat at all. The people who get the new currency first will get to spend it first, before the market lowers the value of the currency. This is a transfer of wealth to them from other currency holders.
Second, as tome suggested, the government would have to take measures to force people to use the currency. This has all kinds of bad effects.
