See, this is why I drag explanations out of people, because you get good answers. I can tick over those links and become better informed.
I thought over your thesis, Crab, the way I am reading it is that you'd raise tax by the exact amount you'd pay back in WFA, but only for specifically those people who are receiving the benefit in the first place? Because otherwise you are taking money out of taxpayers pockets to fund WFA *except* for the person most able to pay - a redistribution of wealth to the old. That lead onto an interesting logic spiral that I typed out below to figure out:
Most of the following is based on a logic chain. It is probably a wonky logic chain. This is, fortunately, not my third year dissertation on a comparison of capitalist and communist economics, so I am OK posting it for your amusement.
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Only the people who don't need the WFA pay it back via the specific tax. Let's call this the Alan Sugar Tax.
Because we're using the word tax, not the word mean-tested, we can pretend it has absolutely no cost to implement. All is well - we get winter fuel payments out of some other public investment and definitely-doing-no-work-to-figure-out-if-we-should-be-taxing-this-person is free. It isn't a payment if they don't have enough money - it is a tax if they have too much! Very different.
And this lead me down an amusing path. (This is a joke, don't take it seriously)
You just raise tax on the entire chunk of people who are as wealthy as Alan Sugar, and only pay back Alan Sugar with the WFA, and there is this big pile of money you can thus spend as the government. Because absolutely everybody except Alan Sugar pays it, let's call it the Not Alan Sugar Tax.
Now you have a big pile of extra cash for the government with absolutely no waste. Tax-and-spend, all very John McDonell. Naturally you and I agree that there is no evidence at all, of course, that government investment is *less* good at growing the economy than private investment, so taxing everyone more is a good thing because it makes everything obviously more efficient.
We're still in agreement? Let's look at the optimal way of applying this logic. The government should own all the wealth, naturally, as only it can efficiently distribute out that wealth equally to everyone, which we naturally need to do because means testing is wasteful. But we immediately should take that money back because the people will spend it inefficiently.
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So my point is this. On the one hand you have the concept that there is a price difference between means testing a payment to a set of people and collecting the same amount in tax from the same set of people. I do not buy that that is not a 1:1 ratio if done properly.
The waste would be in the assessment, but it should be the same assessment to decide if someone is eligible for the benefit or eligible to be taxed. Benefits are, essentially, negative taxation.
As such I think you have conflated 'means testing' and 'bureaucracy'. All tax is means tested. I think youu're actually just relabeling means testing as tax and pretending there is a difference.
Or you are doing what Labour is doing, which is just paying people who don't need it £300 a year out of the pot of taxes and claiming they can't do anything about it, despite having an entire tax system based on figuring about how much money to extract and pump into the economy.