The threat guide is more about his threat to the playstyle, not one v one as this build is more around lane ganks and roaming than individual fights (which in my opinion are something to avoid due to low dps).

I haven't done the maths on that but the team comps I like to play don't really rely on Diablo pushing lanes solo, and either talent is probably more personal preference but as a roaming/gank-cc build the Soul Catcher talent really works well with that style.