No kidding. I had that actual experience of this dispute with my son. I went through such a lengthy explanation of other factors involved, like cars that will be coming soon, predictably, and fast... and he was sticking to a technical position.
At that point, I abandoned "I will explain
everything to my children so they will learn to think for themselves" for "because I said so" -- and got ok with the fact that at that point in time I was really more concerned with their physical well-being than anything else.
In frustration I actually said something like, "well I'm just trying to make sure that you live long enough to have to work this out in therapy." He didn't accept it -- so "because I said so" was my final answer.
(I actually use my willingness to provide a detailed explanation of the situation, if they don't want to take my word for it -- as leverage for compliance at times.
)