Sharing good information is a very good thing. Sharing information that isn't any good, regardless of the intent, is a bad thing.
Your information includes the single lead rule used by the military. It is supposed to provide an easy means of compensation to account for the target traveling laterally to the shooter. The value is that the farther away the target is, the greater the compensation afforded by the rule. There are a couple significant problems with this.
First, your presentation of the rule mentions nothing about it being a rifle-based rule. This rule does not work very well at all for handgun velocities except at close ranges.
Second, the amount of compensation afforded by the rule very well may not be enough. Basically, the "rule" isn't as widely applicable as claimed.
Since this is a miliary rule, let's use the M855 ammo from the M4 carbine. The M855 has a muzzle velocity of roughly 2800 fps and a BC of .304.
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This is rule will give you a dead-center hit on a 15-meter target moving at 7 miles per hour at a 25-degree angle because the target moves .8 inches between the time the rifle is fired and the bullet arrives at the target. A 150-meter target moving at 7 miles per hour at a 25-degree angle moves 8 inches between the time the weapon is fired and the bullet arrives.
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I am going to simplify things by having the target traveling at a 90 degree angle to the shooter and not 25 degree. Given that the single lead rule is a rule of thumb, then the change in degrees should not matter. It should still work, right? It won't.
Using a ballistic calculator, it will take roughly .18 seconds for the bullet to travel from the muzzle to the target at 150 yards. At 7 mph, the target is traveling 10.27 fps. So in .18 seconds, the target will have traveled 1.85 feet (~22"). Putting your front sight just to the side of midline in the direction of travel gives you a 8" lead on the target's centerline. Since the target is traveling laterally to the shooter, the shooter sees the target's side. For ease of calculation, let's say the target profile is 12" wide.
Since the target has moved 22", even with the 8" lead afforded by the single lead rule, the shot will pass behind the target. In short, the 22" of travel, minus the 8" lead lead of the centerline of the target leaves the trailing 6" of target left to be hit. So we subtract that 6" from the distance traveled by the target and that leaves us with 8" of travel not compensated for by the single lead rule. The round will miss the target, passing 8" behind it.
Walking half the speed, 3.5 mph, the target will have moved 11" in the time it takes the bullet to travel the 150 yards. Subtracting the 8" lead leaves 3" of travel by the target and the trailing 6" left to be hit and so the round will impact 3" behind (from direction of travel) the centerline.