"Vagueness" means the rich and powerful can get away with anything, while the rest of us are at the mercy of corrupt judges and prosecutors.
It's also the exact opposite of the "rule of law", which is one of the foundations of a Constitutional Republic.
Vagueness actually leaves more descretion to common law and the people of the jury in determining what is reasonable and what is not resonable than actually putting in hard firm guideless for what is an offense.
Do you live in fantasy land?
Jurors who actually think for themselves are gotten rid of during voir dire.
And those that do make the cut, are told they cannot apply ANY reasoning except that which stated in the law as interpreted by the judge.
Furthermore, information is frequently witheld from jurors, as is the potential sentence for someone if found guilty.
Basically, what your "vague" system has gotten us is a quasi-police state environment, where there are so many laws that no one can obey them all. Where there are so many lawyers and politicians that if someone has it out for you, you are screwed unless you have money. Where minor infractions are now felonies. And where our Supreme Court no longer follows the Constitution.
Which of the two examples better leaves the verdict closer to common law and what is reasonable??
Well, the 30 MPH sign is pretty much meaningless since it was set by a bureaucrat who has never driven that road, and since most people do 40-45 in 30 MPH zones. And the "do not drive fast" is almost as equally subjective.
So I say "not guilty" on both.
And those that do make the cut, are told they cannot apply ANY reasoning except that which stated in the law as interpreted by the judge.
You just made my point without even knowing it.