It is also no secret that during such times commercial banks will work hard to ensure that their clients continue to remain with them. They will also need to work harder to acquire new clients. It can be a time of great competition.
If we want the euro to be strong, there is nothing for it but to comply strictly with the convergence criteria. A weak euro and the attending high interest rate level would be of no benefit to anybody, and that includes the potential derogation countries. Please keep in mind that a monetary union with ill-converging Member States would be incapable of absorbing economic shocks.