I understand where you are coming from. There are many claimants with static conditions that do not require frequent trips to the surgery or substantial medication, but unfortunately DWP decision makers have difficulty understanding this, and assume that you are not ill if you don't need to see your GP or take medication.
It is often necessary to see your GP to obtain sick notes or discuss your benefit claim even if you do not need medical advice, and I often feel that I am wasting my doctor's time when somebody with a much more serious or urgent medical problem would be able to see my doctor, if the DWP did not require me to see him.
I also have ME, severely. For both DLA and ESA I wrote on my forms basically what I suggested earlier, and it didn't cause any problems/wasn't challenged.
I had home medicals for both benefits last year, and we (my friend who was present and I) made the same point to the visiting doctors, who didn't seem surprised. Very sorry to hear it wasn't understood at your medical.