Mr Rock is concerned that advisers are, through the alternative class, unknowingly exposing clients to sectors such as hedge funds which they may not want to be involved in.
As a result, Mr Rock has published a white paper entitled 'What's the alternative; an analysis of the asset allocation of the mixed investment sectors.'
This looked at 477 funds worth £87.4bn within the IMA Mixed Investment sector (0-35 per cent equities, 20-60 per cent equities and 40-85 per cent equities) and IMA Flexible Investment sectors.
Within the mixed investment sectors, 66 per cent was invested in collective investments and exchange traded funds, demonstrating how wide a multi-manager approach is being used. This shows a shift away from a generalist approach to a more specialist approach to investing.

The most significant sectors within alternatives were 22 per cent in commodities, 20 per cent in hedge funds, 17 per cent in absolute return and 14 per cent in property.
Mr Rock said: "The most surprising find was the prevalence of multi-manager funds, given the majority of asset in these sectors sit within collectives. This shows an increasing preference for the diversification and risk managed approach to investing that multi-manager funds provide.
"This white paper will be of great value to financial advisers, who will now be able to understand more fully their clients' exposure when holding a multi-asset fund."