Isn’t that because you don’t have faith in what the EA’s are doing, and/or can’t access a full picture of how they do it?
What I don’t have faith in is the EAs’ ability - or lack of ability, actually - to take into account the human factor. For example, the EA opens a seemingly profitable position, somewhere some news come out, the market panics (if briefly) and that profitable position is no longer profitable. 
1 Like