Life after central banker Batman quits Gotham
Central banks have played the superhero role to great effect in recent years. But what happens if their powers fade? · CNBC

In most superhero movies, a dysfunctional government struggles to maintain law and order before a caped crusader comes to the rescue. For European markets, central banks have played the superhero role to great effect in recent years. But what happens if their powers fade? Are we prepared for a return to the volatility of old and a more challenging path for investors.

Since the global financial crisis, markets have had two principal Guardians of the Galaxy: the U.S. Federal Reserve's Ben Bernanke and the European Central Bank's (ECB) Mario Draghi. They have been supported, Avengers-style, by a host of other central bankers, who have engaged in an unprecedented, coordinated period of loose monetary policy.

But the days of omnipotent central bankers saving the day are over. That old foe, Greece, is dominating the headlines again but the situation now is very different to 2011. While there may well be further easing measures to come, our superheroes' marginal impact will be minimal.

In Europe, the ECB has finally delivered on an expansive quantitative easing (QE) package. However, its effectiveness on the real economy will be questionable. While in the US, QE helped to relax credit constraints for a large part of the real economy, firms in the Eurozone remain more reliant on bank lending. For every 10 euros borrowed by European companies , about 8 euros comes from a bank and only 2 euros from the capital markets. In the U.S., the reverse is true.

Read More ECB ups growth forecasts; will start QE on March 9

The "wealth effect" from inflated stock and real estate prices will also be less pronounced. According to the ECB, housing wealth does little to spur consumption in the Eurozone. Financial wealth has a larger impact, but it is still lower than in the US, where households often own stocks and property for their pensions.

Attention will now have to turn to our elected policymakers and fiscal stimulus to deliver sustainable and inclusive growth.

Unfortunately, fiscal stimulus is challenged by the restrictions of the Fiscal Compact which continue to bind peripheral Europe. For Italy, France and Portugal, limited progress in deficit reduction means even more fiscal tightening this year. As seen by the latest Greek debt deal, Germany will continue to play an important role if countries seek to negotiate their fiscal restrictions. Tensions will persist between governments, as well as within.

While there has been some progress in structural reforms, there is a long way to go. Peripheral countries have successfully achieved greater cost competiveness, but much of this has come through wage freezes and at the cost of high unemployment, which for the euro zone overall persists at above 11 percent. Labour market reform still remains a high priority, and youth unemployment is particularly worrying. In Spain, more than half of the population aged under 25 is without work.