Hi Peter!
Looks like Monkey had a pretty good day, getting some movement down to blues from the 3.25U. That's great!
I don't think it's meter error. +/- 25% is a bit high (they're not supposed to be off by more than +/- 15%, and that's bad enough!), but it's not enough to make that big an error. If the 70 had been a single green number in a sea of red and black, I would think it more likely that you got a bad strip or the meter just flubbed it, but Monkey had a very clear curve yesterday. He might not have been "truly" at 70 because of meter error, but he was still pretty low no matter what.
Withholding food, particularly carbs, during the day can definitely make a difference, especially with Caninsulin. They really need some food to act as a buffer, and in Monkey's case, it seems likely that what he's eating right now is playing a very big role in keeping his numbers up out of the danger zone.
Poor little guy! Losing weight rapidly isn't a good thing, we want to get his weight back up. About dry food: we have a bit of a conflict happening right now, because the rapid weight loss is likely due to his uncontrolled diabetes, and dry food certainly won't help with that! However, while we're figuring out the insulin situation, the dry food will give him some extra carbs and help keep him safe from hypoglycemia. That's the primary reason we recommended leaving dry out last night.
How is he acting today?