I'll try my best..
In the 18th century when the Kind of England taxed windows, human nature being human nature, people began to brick up their windows. I'm imagining they even built houses without windows to save a few pence on the tax. Ultimately, in response to the tax, people would have hid, boarded up, or concealed their wealth by building homes with fewer, less, or probably in the case of the Irish and Scots, homes with no windows.
The second part, I believe, is if the counting of windows is used by the State to determine wealth, the data, that is, the counting of windows would create a weird model. Even though the windows might indicate some degree of wealth, they really wouldn't represent wealth. The Tax-man would have a helluva time trying to figure out where real income resided based on the measure of only windows. And daily reports on CNBC of the National Window Index would have nothing more to do with real incomes than the number of walls or faucets in any particular bungalow.
How am I doing?