It makes some sense as judge as arbiter and interpreter of law, no? If a judge were to say "You should argue this" then the expectation that he or she would be

It makes some sense as judge as arbiter and interpreter of law, no? If a judge were to say "You should argue this" then the expectation that he or she would be predisposed to finding that a valid claim would be pretty apparent. I can see examples where this would lead to slippery slopes in both the defendant's and plaintiff's favors.