It’s not about complaining about how they vote. The jury doesn’t have complete freedom because that’s the aim; they have complete freedom because there’s no other way to do it and still have a the concept of a jury. They are supposed to follow the directions of the judge in terms of how to apply the law. Telling them, “no actually you don’t have to do that” is definitely dodgy, no matter the technicalities of how they de facto can choose what to do.