A still body hides part of the wall, part of the floor and, for a moment, the ball. How much depends on your stance and, far more, on how close the receiver is.
Read this by court
What a body hides is the same on every court. What it means is not. On one-wall it is your block. On three-wall, four-wall and 60×30 it is what you have to get out of the way of: see how the courts differ.
The body in the sums
Figure 1. Geometry: the player in the sums, seen from behind, feet on one spot in all eight. Sizes are on the numbers page, and can be changed.
Figure 1 shows the player used on every page of this guide. In each pose the feet stay on one spot, because that is the point: these are the shapes you can make without moving your feet. The wide lean, left or right, is a wide stance with the body tipped over it.
Distance matters most
Figure 2. Geometry, seen from above: the dark wedge is the floor the hitter hides from the receiver's eye, and the thick line is the stretch of front wall hidden. The hitter has not moved; only the receiver has.
Hold your thumb up at arm's length and it hides a person across the room. Hold it near your eye and it hides the room. Your body does the same to the receiver. In Figure 2 the hitter does not move. With the receiver 4 feet back, the hitter hides about 10 feet of the front wall. With the receiver 12 feet back, only about 5 feet.
So you hide the most from a receiver close behind you, and a receiver who drops back gets a much better view. The receiver can buy sight by giving up court.
What each stance hides
Figure 3. Geometry: the 20 by 16 ft one-wall front wall as the receiver sees it, 4 ft behind the hitter. The dark area is hidden. The legs do not show here: from a ready crouch the line past them reaches the floor before it reaches the wall.Figure 4. Geometry: the share of the one-wall front wall, and of the floor between the wall and the receiver, hidden from the receiver 4 ft and 12 ft behind the hitter. A lean to the left or the right gives the same share, only on the other side, and so does a wide lean.
A wide stance is not there to hide the wall. Its main job is to make the receiver go farther to get round you, which is on the return lanes page. It has a side effect here: you do get lower. Spreading the feet lowers the hips, so the head and shoulders come down, and those are the parts that hide the wall. In Figure 3 the wide stance hides a smaller block of wall than upright. The legs do not show on the wall at all: from a ready crouch, a line of sight past the hitter's knees reaches the floor well before the wall.
What a wide stance does cover is the floor near you, as Figure 4 shows, and the low balls coming through it, because each leg throws its own shadow.
A lean does not hide much more than upright. It moves the shadow. From 4 feet, a lean to the left sends the shadow out to about 8 feet left of centre, where upright reaches about 5. That is why one-wall players hold those awkward positions: not to be bigger, but to put what they have across the line that matters.
A wide stance with a lean puts the two together, and the numbers say it is a lower body, not a bigger one. From 4 feet the head is down to 5.3 feet, so it hides about 11% of the wall against 17% for a plain lean and 19% upright. Yet its shadow reaches as far to the side it leans as the plain lean's does, and its middle moves a little further: about 3.4 feet against 3.2. It hides the most floor of any shape, about 24% of it against 22% upright (Figure 4), and its legs are those of a wide stance, so the gap between them is still there (Figure 11).
How long the ball is out of sight
Figure 5. Geometry, one-wall, seen from above: a drive at 60 ft/s comes back past the hitter. The dotted part of the ball's path is hidden from the receiver, the solid part is in sight.Figure 6. Geometry, one-wall: the seconds a 60 ft/s drive is out of the receiver's sight on its way back, for how far from the hitter's feet it passes. Each line is a receiver straight behind the hitter.
This is the number that matters most to the receiver. With the receiver 8 feet behind you, a drive that comes back 1.5 feet from your feet is out of sight for about 0.27 of the 0.61 seconds it takes to arrive (Figure 5). The receiver loses close to half the time there is to read it, and sees it first about 11 feet from the wall. The same drive 4 feet to the side is in sight all the way.
Figure 6 shows the same thing for three receivers. The closer the ball comes to your body, and the closer the receiver stands to you, the longer it stays hidden. A receiver well back loses it only when it passes very near you. The receiver also misses most of your shot on its way to the wall: at 8 feet, about 67% of that flight is behind you, so the first clue to where it is going is late as well.
On one-wall this is the advantage of a ball that returns close to you. It is hard to see and hard to hit, and you have earned it by where you played the shot. On three-wall, four-wall and 60×30 the same picture is what you must not leave the receiver with: you yield position and give a clear view, and a ball too close to you to see is a screen and a replay.
A check from the four-wall book
Figure 7. Geometry, seen from above: the book's check for a screen serve, drawn for a server in the middle of the zone. The thick line is what the server hides at the spot the book names, for a ball 4 ft up.
The four-wall book gives a real test for a screen serve: a receiver in the centre of the rear court, two to four feet from the back wall, "should have a clear view of the served ball as it rebounds from the front wall when it is approximately five feet in front of the service zone." In Figure 7 the receiver is 3 feet off the back wall. At that spot, a server in the middle of the zone hides a stretch about 2.5 feet wide, so a serve has to pass close to the server to be screened from there. The GAA book has a screen serve for its courts too (its rule 4.3). The one-wall book has no such check.
Next: return lanes, the same geometry from the receiver's hand.