Not, like, literally harmful to your body. 
Generally — in sports, in learning other instruments — we’re taught to avoid repeating motions that we want to unlearn. “Practice doesn’t make perfect, it makes permanent.”
But then there’s Andy Wood, hopping away until he hits the appropriate speed. And in the more recent CtC videos, it seems like the whole ‘start with speed’ thing is explained in the sense of that faster motion being effectively a totally distinct technique from our slow-motion mechanic.
I’m now totally a believer that slowly inching up the metronome won’t ever make you go fast — I have nearly forty years of failure to document it! But my question for Troy and the rest of you:
If fast picking and slow picking are truly separate circuits and you can’t use one to develop the other, then is there any particular harm in continuing to use your inefficient hopping motion while doing things like memorizing left-hand fingerings or learning scales or just making music while you develop your faster mechanics through CtC?
Since the original CtC series taught me to recognize string hopping, I get frustrated/concerned anytime I notice my right hand hopping away on something difficult…
Can I relax? Is there any danger in continuing to reinforce (“groove”) a sub-optimal movement?