Depends on the dissent. Sometimes, the dissent adopts the minority rule, and on occasion, the minority rule has since become the majority rule.
I've had a professor specify on an exam whether you are in a minority or a majority jurisdictions, so the minority rules have been very important.
So read the dissents and concurring opinions. If they're just disagreeing with how the majority viewed the facts, I wouldn't worry about it much. BUt if it takes another view of the law, I'd make a quick note about it.