Growing up, in many group chastity lessons, inevitably someone would ask the seminary teacher, or the unlucky bishopric member, a question of "is ___ allowed when I'm dating?" This frequently led to a response of "If you have to ask, the answer is probably no."
This led to youthful me feeling very frustrated. As the oldest child with 4 younger sisters, discussions like this were not frequent in our home. I don't fault my parents for that, but being told that if you had a question about what you could and couldn't do meant that you shouldn't be doing that thing was very confusing. Even though I knew that couldn't be right, every time I wondered something like that I had that guy in the back of my head saying it must not be good then. Not the Holy Ghost. The really otherwise-nice bishopric member.
I think what they mean, or rather should say, is "Here are the clearly stated things you should and should not allow while dating. That specific question might be better to discuss with your parents, where you can come to a conclusion after a thoughtful and personal discussion with people who know you, know your strengths and weaknesses, etc".
I was reminded of this today when talking about keeping the Sabbath holy in Sunday school, a class member with more weight to his words announced that if you are wondering if doing something is acceptable on the Sabbath, it probably isn't.
What if you are a new member and are unsure if leaving your house to visit your sick grandmother 100 miles away, because you might have to purchase gas, is in line with Sabbath day observance?
What if you are a healthcare professional, or a police officer, or just got a random job after a long bout of unemployment, and conditional on retaining the job is that you work on Sunday? And you're pondering what the right thing to do is? The answer is not automatically "Do not do that thing because you're wondering about it."
Or what if you make poor Sabbath day observance choices, but never think about it? Does that mean you're good?
It's not a great message, in my opinion, to spread.