- Comparing adjusted disposable income between Scandinavia and the US is highly misleading. The disposable income in Scandinavia doesn't need to cover any healthcare, education and other public services. I wonder how much, if any, the difference is once you adjust for that.
- The argument mistakes distribution of wealth with average output per capita. Portugal is in the bottom of the list in the GDP per capita comparison between US states and EU countries. In Portugal there is a somewhat high wage disparity which means that those with high wages can afford to pay those with low wages to get cheap pizza (the example given). The same disparity exists in the US and pizza is cheap too, even though the US GDP per capita is at the other extreme of the comparison. Scandinavian countries have low wage disparity so things are more expensive by comparison. It has nothing to do with the output of the economy.
Basically it is trying to draw conclusions about the strength of the economies based on statistics that don't properly control for very relevant factors. The only good argument is the 2.2% vs 3% GDP growth rates. Considering the article is from 2005, recent events may throw some doubt into that picture. The latest estimates on Wikipedia were 2.6% in Norway and 1.1% in the US.