Just some personal observations and thoughts:
I have 2 major vertical surgical incisions in my abdomen from many years ago. I had gone to 2 different acupuncurists who both also did cranio-sacral therapy. I had gone to them purely for fun- to see what it was like, and for balancing.
They both said that my abdominal energy lines (do not know if they were referring to meridians or not, did not ask) were askew. They used the needles and their c-s skills and energy to address this (in re-aligning? did not ask). This was over several sessions. I do not know what the meridian line result was (i.e. straighter?), but I do know I felt different, both after sessions, and between therapists..
However, my experience is that these 2 acupuncurists were not equal in skills despite the same degrees. Both had same level (M. Ac) and identical c-s training. One had pure spiritual energy, needles never hurt, calm, quiet, soothing. Resulted in emotional release, looseness/flexibility in joints, feeling great, deeper breathing, generally overall fluidity.
The other one was a bit earthier in approach......"just breathe in to the pain".........suuure! Stated she could feel the distortion in energy lines around incision. Did not have as "refreshed" feeling afterwards. But boy could she dig up some stuff which did not erupt til a few days later! Whew-where did that come from!
Based on what you were asking (physical nerve location vs. traditional meridian line), I wonder if it is less important than the sensitivity of the acupuncurist in locating the energy line. They placed the needles according to touch, once the general area was identified. If they do not have the sensitivity, perhaps the needle would be misplaced, leading to pain and perhaps ineffectiveness (speculation there).
The same goes for the cranio-sacral part. They would put one hand on one area, and the other in another, perhaps to re-align, strengthen, whatever (did not ask, too relaxed at the time).
I think the neural pathways and meridians are not always on the same course. One could do a search for images to compare. Also, existence of phantom limb sensations might suggest that the two are separate and unique.
One can only undergo the experience a few times to draw personal conclusions; perhaps it is an individual thing, depending on the area of damage!
Robin