They absolutely have differing effects, just like different sports can produce generally fit athletes with different specializations in musculature and skill se

They absolutely have differing effects, just like different sports can produce generally fit athletes with different specializations in musculature and skill sets. Furthermore, directed focus is not strictly necessary, depending on what you mean. There are techniques that do not entail keeping the attention fixed on one object, though in my experience attentional control is super important. Shinzen Young has a talk on YouTube where he discusses the flavors of enlightenment as they differ from lineage to lineage. I'm not aware of research, however, that compares the effects on tradition/technique to another, though there may be some out there.