Several brokers also note other reasons to bet on France at the expense of Germany - including that CAC-40 firms are less exposed than those in the DAX to sales in emerging markets, where growth forecasts are being revised downwards.
Then there are labor costs, a longstanding issue in French competitiveness. Here, Bokobza cites the importance of a freeze on civil service pay which is a part of the Hollande reforms.
With the public sector such a major economic force, this amounts to a freeze on France's wages benchmark, he argues.
By contrast, German plans for restrictions on temporary contracts and the introduction of a minimum wage "would be steps in the wrong direction for German competitiveness".
The Credit Suisse team led by Andrew Garthwaite set out similar arguments on labour costs, downgrading Germany along with its French upgrade.
France has already taken steps to reduce the effect on profits and figures published by Germany's federal statistics office suggest these policies - perhaps along with French unemployment running at over 10 percent - are having an impact.
French labor costs grew just 0.4 percent in the third quarter of 2013 from a year earlier, against an EU average of 1.0 percent and a 1.9-percent increase in Germany. Non-wage labour costs actually fell 2.4 percent in France, against a 0.3 percent rise across the EU and a 1.0 percent rise in Germany.
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French unit labor costs nevertheless remain a key concern for rating agencies: "Despite generally weak export performance since the onset of the 2008-2009 global financial crisis, wage increases have outpaced productivity," S&P said in April.
Eurostat put French unit labor costs in Q3 2013 17 percent above 2005 levels while Germany's were ahead by only 10 percent.
Nonetheless, some argue that French stocks offer good value.
Credit Suisse calculates that Paris equities are trading at a 25-percent discount to their 20-year average based on 12-month forward price earnings over normalised return on equity. German stocks sit right on their 20-year average at the moment.
French equities have already outperformed Germany in the year to date, according to Thomson Reuters data that adjusts for the different treatment of dividends in the two indexes.
But the argument for longer-term gains on the back of new economic growth is not yet won. Doubters question whether Paris can persuade Berlin to adopt a slacker, pro-growth deficit policy for the euro zone. And political disputes over targets could be a new blow to investors' confidence in the EU system.
"If those differences persist on how to get growth going in the euro zone," said Alexandre Baradez, chief market analyst at IG, "That would point to renewed tension in the market."
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