Reading history is interesting, reading rules can be a "rewarding" chore (there is always some pain involved) being part maths and part logic, but then sometimes something as strange as the evolution of an Order of Battle provides more curious insights, reflecting on "what happened" over time.
Consider the Chain of Command WWII Soviet Rifle Platoon Order of Battle ... imagine you are a Soviet NCO junior section leader. When war broke out (Barbarossa 1941) you commanded eight rifleman and a LMG pair (and there were four sections to a platoon commanded by a Senior Lt Leader). By end of July 1942, in each section, two of those rifleman had been killed and not replaced [25% down on a full pre-War complement]. Then comes along a cauldron like Stalingrad. My forces (a full Soviet Rifle Platoon) start on the "friendly" Russian bank of the Volga looking across the river into the fiery maelstrom that is now Stalingrad. The campaign starts with 3d6 casualties from this "daylight" crossing: I roll a 6, 6 and a 1 which equals 13 dead, MIA or wounded. Urggh not a great start (see below, black shaded area indicate pre-Stalingrad "wear and tear" on Soviet formations up to this point, the scored through circles casualties because of 'enemy fire' on the Volga crossing, obviously a barge or two took a direct hit!):
There were "thirteen" casualties (horrendous in other words), spread across four sections, which means taking away 3, 3, 3, 4 soldiers respectfully. I deplete each section's riflemen accordingly, leaving the LMG teams and Junior SMG leader intact. Boy does this look "fragile"! I then decide to disband one "fragile" section to "pump-up" the others. The first section gets the LMG team and two rifle troops, the second section gets a rifleman and the third section gets the demoted Junior Leader - probably now wielding a rifle (see below):
The battle damage to the platoon means it is probably 'en route' to the later Stalingrad Order of Battle where sections start to reduce rifles and bump up their LMG content to two where possible!