In 1972, the year the Lakers won the championship, the First Presidency issued a statement counseling against the use of caffeine drinks. It was counsel, not a commandment. But I wonder if their counsel should not be enough for us. Strictly speaking, caffeine drinks are not against the letter of the WoW, but perhaps they are against the spirit of it.
Yes, you are right--counsel is counsel and not a commandment. I think that it would nice if we did not need to be guided in all things, but if the Brethren offer us counsel, I think that we should think twice before rejecting it.
There is no policy, law or commandment that says we should not drink Coke, so why even make it a state of worthiness. From a totally health angle Coke as well as other soda drinks should be given up totally, but that's a personal position.