It's a good skill to have, and is very helpful to predict which areas will have moving SL gates and which will have moving SG gates. Having that skill allows you to plan your route on the fly so it avoids having to slow down via speed control turns, or lets your slow down via speed control turns while avoiding hockey stops, or taking other drastic moves.
However you still have to be ready willing and able to make those moves; you have to be ready for any physically possible moves of the other skiers on the hill to stay safe.à
It's a lot like driving/motrocycling in traffic. Be ready for that guy to pull out in front of you, or turn left in front of you.
Speaking of riding a motorbike, the left turner in front going the other way is the hardest to deal with. Slow down too much and you are inviting him to turn in front of you. Speed up too much or keep your current speed and you might not be able to steer a path around him when he does. What to do? What to do?