Hi Patt,
Question - how much does Neo weigh? Does he get 1/4 can at each meal (you feed 4 times a day, right?). I'm wondering if he would eat more if you let him. If he's maintaining his weight, then it's enough food, so not a problem. I have a cat named Mullet, who isn't diabetic, that eats Friskees too, and he's around 11 pounds. He eats about a can and a half of Friskees Pates a day. My diabetic, Bob, eats two cans of FF classsic, and the other half of the Friskees can. He's about 14 pounds. It isn't really the "ounces" that matter, it's the total calories a day. The one can a day, depending on which flavor(s) might be enough calories for Neo. But a diabetic cat tends to eat more at first, because they can't get the same amount of "bang for the buck" as a non-diabetic does. They don't metabolize the food as efficiently.
Good call on not shooting. Like I said earlier, you'll probably get a higher number in the morning due to no insulin for 24 hours, but don't worry about it. The higher number would be expected. If it isn't higher, that's even better! It means his body is trying to regulate itself by producing some insulin on its own. That would be a very positive sign.
Carl