How many nerves are you memorizing?
One thing to remember is that a lot of muscle innervation is compartmentalized. For the leg, for example, there's an entire 3 nerves that controls everything (Tibial nerve controls the posterior portion, deep peroneal nerve controls the anterior muscles, and the superficial peronial controls the lateral muscles). Similarly, the thigh has the obterator (medial muscles), sciatic nerve (really a combination of the peronal nerve and the tibial nerves. Posterior thigh) and femoral nerve (anterior thigh). There are a handful of exceptions, such as the hamstring portion of the adductor magnus, but this will be the majority of it.
Dermatones, on the other hand, is the work of the devil.