I wouldn't focus on a chain of authority and who is deferring to whom unless it made absolute sense to do so (I expect I'd go with a cautious neuro who had to clear meds for example).

Without that, as you mentioned before, it is indeed a decision which someone should make after looking at the research and doing a risk-benefit analysis.

Even without reference to MG, there has been some new research and discussion recently about the relative benefits and risks of statins which is worth skimming. in the following link, there are references to differing results in competing studies:

http://www.nejm.org/doi/full/10.1056/NEJMc1207079