Were Cyprus banks really in trouble before they were forced to mark down their greek 5 and 10 year by 40%? If anything the lesson here is a responsible bank can't hold debt that's backed (directly or indirectly, like laiki) by the ECB unless it's german.
The lesson is presumably that a bank should spread its bets. Here's the Central Bank of Cyprus in December 2012:
When one invests over 100% of one’s capital in a single
financial instrument – even if that instrument is considered
low risk – it is indicative of poor risk management.
[..]When bankers do the same with investors’ money –
because their bonuses are linked to short-term income
while the losses are underwritten by the taxpayer – the
same behaviour is more than just poor risk management – it
is ‘casino banking’. [1]
