ED is the clear winner IF you are an elite player and IF the encounter is perfect for ED (pure single target, low movement) AND the encounter is bad for IFE (does not allow any extra uses). Correct. That just doesn't happy very often.
ED and IFE has different strengths, which is good, but we need to dispell the myth that you can't do competetive ST without ED (especially in 7.1.5), because that simply is not true, as IFE is very close (or better) in most cases, and for the average player IFE is almost always better.