Over the past few years I have watched what used to be slightly cranky criticism of the fund management industry go mainstream. The recent call from the Financial Conduct Authority and the Department for Work and Pensions for evidence on transaction cost disclosure in pensions is just the latest example.

Debates about broker commission, best execution and cost disclosure were once seen as arcane matters of little concern to investors. And rightly so: statistical study after statistical study has demonstrated that the impact, if any, of trading costs and the rest is negligible. Net returns - the ultimate litmus test - on average equate to the market return, less direct fund management charges, with no further drag from transaction costs. Objectively, this should not be a concern.