My weakness tends to wander around like you are saying. My hands usually do pretty well. Some days my voice totally goes and my ears get all weird. My legs may not be all that weak at those times even though I do notice that I may drag a foot a bit. Other days (like today) my voice is not that bad, but my legs are weak. On occasion my neck gets all weak and weird. My vision blurs pretty consistently in the evening and my eyelids, though always droopier than I would like and asymmetrical, sometimes they are not that bad. Other times they are totally flopped and it is hard to see out. If I get behind on my mestinon dose, it all gets worse. But the whole process wanders around.