Any direction may cause “over-doing”. So, people need to have lessons. However, probability or likelihood to make an ideal state happen will be different by directions.
We are more likely to be in an ideal state if we have a clearer goal (or objectivity). In other words, we had better give instruction as specific as possible.
Direction of “up” will be different by people. Someone thinks “up” and could end up his head tilting backward. The direction of “up” for this person’s mind includes a bit backward direction (or tilting).
How to be specific? First, we need to know a line to get a direction. This is simple geometry. We need two points to make a specific straight line. So, we have to have “another point in space” other than “the head” (or “the top of the head”) to make the direction more specific. The another point in standing condition will be the bottom of the feet.
So, direction like “the top of the head is going upward against the bottom of the feet” will be more specific (true “up”), and this will actually help people to carry out an ideal state by themselves.
I use this direction personally and in lessons. There seems successful so far. Again, some people may do it too much by this direction, but its likelihood may be lower.
If the upward directional component is adequate, we don’t have to add a linear (vector) direction of “forward”. I add a rotational direction of “forward”(“Turn the forehead forward moderately”, or simply “Turn the face forward”).
Having “a reference point” (the bottom of the feet in this case) is helpful. That is why I think of the bottom of the feet first. Attention to the support part is primary to “primary control” for me.
I mentioned this “over-doing” issue in another blog post. This is about over-doing of the direction “forward”.