The military standard for coordinating a time-on-target strike is plus or minus three seconds from the prescribed time of impact.
With the advent of "smart" munitions and more accurate firing technology, CEP is now less of a factor in the target area.
A technique called "Time on target" was developed by the British Army in the North African campaign at the end of 1941 and early 1942 particularly for counter-battery fire and other concentrations; it proved very popular.
It relied on BBC time signals to enable officers to synchronize their watches to the second.
[2] The U.S. Army conducted a "Troop Reaction and Posture Sequencing" test in the 1970s to determine how fast soldiers in a hasty defensive position can achieve degrees of protective postures when faced with artillery fire.