EC stacks have been shown in multiple studies to aid in LBM retention. Norepinephrine (which mediates its effects) has also been shown to be anti-proteolytic.
So, typically, the answer is a very strong "no".
However, catecholamines have been shown to decrease leptin levels, so possibly at very low bodyfat, EC could be counterproductive, but there is nothing to really suggest one way or the other.