For most lay investors, figuring out how to allocate money presents a dilemma. A dizzying maze of experts, investors, fund managers, and advisors exists to allow people to outsource their questions to a financial professional who can make responsible decisions on their behalf to grow savings. But to reliably figure out who won’t rip them off or make bad calls, regular people have to know so much that they could almost invest the money themselves in the first place.Finance writers and others in the guidance-giving business offer some shortcuts to try to keep things simple. These range from the objectively...