I know you are not an ID proponent, but since you are "not an atheist", I figured you at least acknowledge the possibility of an intelligent designer.
My scientific opinion is that the amount of evidence necessary to conclude the impossibility of anything, including an intelligent designer, is unattainable, and that anyone who lets their religious beliefs in some way inform their scientific judgment is being unscientific.
I would think that any ID hypothesis would necessitate a discontinuity. Genomicus stated that:
the presence of a discontinuity in the biological universe is one hallmark of intelligent design,
And in Message 156
he mentions front-loading, which I was assuming requires a discontinuity no different than normal mutation, since front-loading is superfluous if it requires the same kind of periodic intercessions by the designer as non-front-loading possibilities.