and this statement (based on the Rowland article which I couldn't find on line) doesn't make physical sense to me when I multiply by "factors of ten":

A few studies are quite insightful. It appears that a soldier’s ability to hit a given target is typically reduced by a factor of ten or so when he is moved from a static rifle range to a field firing area where he has to select cover, move, shoot and so on. It is reduced by a further factor of ten or so if there is an enemy firing back at him. It is reduced by another factor of ten if the enemy has machine guns, or if he has tanks; and by a hundred if he has both. [1]

[1] D. Rowland, The Effect of Combat Degradation on the Urban Battlefield. Journal of the Operational Research Society, Volume 42 No 7, 1991
Posit a rifleman who at range consistently shoots 100mm (4") or under, 5 shot groups at 100m (Storr, p.2). Thus, the following table using the "factors of ten" from the Storr article:

1. 100mm (4") - firing at range

2. 1000mm (40") - firing when executing fire and movement (3.3 feet)

3. 10000mm (400") - same as # 2, but under enemy rifle fire (33 feet)

4. 100000mm (4000") - same as #3, but adding enemy MGs or tanks (330 feet)

5. 1000000mm (40000") - same as #3, but adding enemy MGs and tanks (3300 feet)

For the last one, this exercise in multiplication yields a 1000m envelope at 100m distance to target. This doesn't seem to make physical sense.

Any idea of what Storr/Rowland means by a "factor of ten" ?

PS: The concept of Combat Degradation would seem to be very relevant to development of sensible ROE/RUFs and the need to train with them under realistic conditions.