Common sense and intuition are really useful in all kinds of everyday situations. When it comes to Access and Inclusion though, the right thing to do is often counter intuitive. For example, if you have to physically guide a visually impaired person from A to B for the first time, you may assume that you should take their arm and gently steer them to where they need to go. However, as a visually impaired person I can tell you it is very scary being pushed through the world ahead of someone. It is much better to ask the visually impaired person how they want to be guided. Often they will want to take your arm and walk half a step behind you. In that position they can relax more and simply follow your movements.
Similarly with guiding a visually impaired person up and down stairs. Most people instinctively want to count the stairs and tell the visually impaired person how many there are. It just seems to make sense. However, believe it or not, many people don’t include the top and bottom steps when counting, so it can be misleading and potentially dangerous. The really important thing, which most people don’t think to mention, is whether the flight of stairs is going up or down!
I could give more examples of misguided common sense ideas about people with other impairments. For example, the idea that it is appropriate to communicate with deaf people by shouting at them. You probably get the point by now though.
Common sense is no substitute for high quality training, delivered wherever possible by the people directly concerned.