@KL, yes I agree. When you look at the holdings in any say LS, there are holdings at less than 5%. You have to wonder what good is that but the list makes for a sophisticated impression.
I have used both LS and the global strategy funds as general equity holdings when I couldn't really make my mind up, so I bought GS Dynamic when my wifes ISA had spare cash, and LS 40% in lieu of a mildly defensive holding.
So they are a good way of avoiding the temptation to tinker or be forever ever adding to the list of holdings. But yes, if the fund has holdings of less than say 5% you do wonder if it's more for the appearance of diversification and sophistication rather than a likely real benefit.
For my SIPP I am doing my own mix and not using these. I was tempted to use a multiasset fund as a core holding and to build around that. However it became clear that I would end up holding a number of overlapping funds so decided to construct my own.