I'm in two minds about Nick Clegg's call for greater employee ownership.

On the one hand, he's right to say that such firms 'often perform better'. There's good evidence that they are more productive than orthodox capitalist firms and are just as likely to grow. This isn't simply because employee owners are more motivated than ordinary workers. It's also because in a world of bounded rationality and knowledge, the pursuit of growth and profits might be something best done obliquely rather than directly.

But I have two quibbles.

You might think that one of these is that companies sometimes need to raise more capital than they can get from workers investment alone, and so need external owners.

Not so. Between 2003 and 2007, UK companies were actually net buyers of shares, not sellers; they only became issuers in 2008, when banks needed to boost their capital bases. The stock market, net, is not really a source of capital; for most mature firms, growth is financed internally.

Instead, my problems are elsewhere.

One is that a little bit of employee ownership might not be enough to have the 'hugely transformative effect over corporate culture' that Clegg desires. Bear Stearns and Lehman Brothers had large employee shareholdings - so did Enron, come to that - but both were incompetently and capitalistically managed.

Secondly, employee share ownership violates the first rule of investment - don't put all your eggs in one basket. The worker who owns shares in his employer is risking not just his human capital but also his financial capital in the same venture. This is dangerous.

Granted, there's an upside to this concentrated risk; the possibility of big losses can be a good incentive. But if this possibility is not accompanied by genuine control, then we have the worst of both worlds; workers take risk, but not power.

Herein, I fear, lies a blind spot that liberals have long had. They've long thought that the middle way between left and right is better than either. But it might be worse.