Below is a chart that summarizes data provided by the OECD on productivity, compensation and unit labor costs. I computed the accumulated change from 2000 to 2013 (except for the US where there was no data for 2013, so the period is 2000-2012).
The blue column (real GDP per hour) represents improvements in productivity. This is the ultimate source of sustainable improvements in living standards. What we see is a significant gap between the US and Europe (more so if we consider that the US is 'missing' one year). When we look inside Europe we see a big outlier: Italy, where GDP per hour has barely changed in the last 13 years. There are some interesting differences among the other countries with Spain seeing an 18% increase over the period compared to 15% in Germany and 12-13% in France and the UK. In this first column, there is no obvious German miracle during this 13 years.
The second number is labor compensation per hour. This is measured in nominal terms (i.e. current Euros or US dollars or UK pounds) as it should be when talking about competitiveness. One expects that increased productivity gets reflected in increased compensation (in real terms) and in addition we should see the effect of inflation. Here Germany stands out as the country with the lowest wage increase (per hour). To make sense out of this number we should compare it to the increase in productivity as measured by GDP per hour. This is what the third column, the unit labor cost (ULC) does, it is simply equal to the change in labor compensation per hour minus the change in output per hour.
When looking at ULC we see that Germany has seen the lowest increase in labor costs per unit of output but not because of the highest increase in productivity but because of wage moderation relative to productivity gains. Italy and the UK are the countries with the largest increase in ULC through a combination of zero (Italy) or average (UK) productivity gains combined with significant wage growth. This is the German "miracle", the ability to convince workers to get paid less (relative to productivity) than in other countries. This is good news for German firms.
To make the "German miracle" look even stronger we can replicate the same analysis for the pre-crisis period (2000-2007).
So can low wages be the solution for some of the Euro problems? If the goal is to improve living standards, the focus must be on improving GDP per hour, that is the only way to ensure sustained progress. Having said that, for a given increase in GDP per hour, wage growth has to be consistent with these improvements in productivity so that unit labor costs do not grow too fast, otherwise a country will be pricing itself out of the market (and we will see that in a decline in the number of hours, unemployment)
Finally, the connection between wages and prices is also not as straightforward as some would argue. The numbers for labor compensation above are all in nominal terms, which is the right way to compare labor costs across countries and its relationship to competitiveness in global markets (more so when we compare two Euro countries so we do not need to worry about exchange rates). But the evolution of nominal wages can be very different from the evolution of real wages. Below I reproduce the first chart (excluding the UK) where I adjust wages and ULC for domestic inflation (using CPI).
If we compare Germany to Italy or Spain now we see that real wages did not grow significantly faster in Italy or Spain than in Germany, and this is of their higher inflation. When compared with GDP per hour we could still argue that real wage is high in the case of Italy but it looks as low in Spain as it does in Germany. Notice that when real wages grow slower than GDP per hour it must be that we are seeing a decline in the labor share, so an increase in the capital share. In other words, prices are not only related to labor compensation but also to profits.
In summary, no doubt that wage growth can in occassions be excessive and generate increases in labor costs with negative consequences on labor market outcomes. But insisting on moderation in wage growth regardless of the circumstances as a recipe for growth is not right. First, sustained growth in living standards can only be the result of increases in productivity (otherwise, why don't we just make wages equal to zero to maximize our competitiveness?). Second, what matters for competitiveness is prices and those depend not only on labor costs but also on the pricing power and decisions of firms. Excessive wage growth might be a drag on competitiveness but so can an excessive increase in profits or other forms of rents.