Eurozone Q2 2010 Economic Growth: Economists have warned that the expected report on Friday of strong economic growth in the single currency area in the second quarter, should bring to mind an old adage in the world's most popular forecasting sport - - the weather - - where the elders keep reminding us that one swallow does not make a summer. The same holds true in business cycle forecasting: one bumper quarter does not make a robust recovery and investors are advised not to read too much into what likely was a very strong economic performance in Europe during the second quarter.  The European economy is not expected to be able to keep up the pace it showed in the April to June quarter.