From my understanding, the allied approach focused more on the rifleman, with less emphasis on the machine gunners.
That's understandable when you consider that the Germans were defending and the Allies were assaulting. It's not that easy to maneuver crew served weapons in the assault.
In the assault, its not just the rifle but the Squad Automatic Weapons. In WWI, we didn't have SAWs, Our troops were issued the French Chauchat, which was a machine rifle, but it didn't really catch on with our troops. The Chauchat was a long recoil type action as opposed to gas operated, and was prone malfunctions. Several spare parts were required to be carried by the gunner.
Regardless, any machine rifle (or SAW), not withstanding being an asset to the rifle squad was no match for the entrenched crew served MG's across no man's land. So WWI ended up being a war of attrition. Who had the most troops and national resources won. That being the reason that the Russian Collapse on the Eastern Front gave the advantage to the Germans, who lost that advantage when the US entered the war.
WWII was a different war, MGs didn't play the part they did in WWI, yes they were effective, but WWII was more of a war of maneuver as oppose to being static like WWI.
The US, understanding the need for SAWs, and their experience with the Chauchat, turned to Browning for the BAR, which was quite effective. Plus the fact that the fire power of the Garand assisted the BAR in fire power, allowing infantry troops to maneuver against stagnate MG positions.
Also you had the mech. infantry and armor you didn't have in WWI, which negated the abilities of the MG.
The US tried to replace the BAR and M1 with the M14 and E14E1. Good ideal but the M14E1 was too light and too hard to control in full auto. At the Same time the M-60 was adopted. It was a GP machine gun, meaning it could be used as an SAW and Crew Served MG. It was basically a copy of the German M42 family of Machine guns.
I was a machine gunner a good deal of time as an Infantryman with the 2/502IN 101st in the RVN. It was an effective SAW, and also in fixed positions it worked with as a Med MG, while set on it bipod. However most of the MG use in that war was with the '60 being used as a SAW.
The problem as I saw it, in Vietnam was the use of the Bipods on the M-60. Even set on the lowest position they tended to shoot high. The reason being, is soldiers tend to want to get low when getting shot at, so the gunners would get down behind the gun as low as possible meaning they would be shooting over the Indians who they are tying to engage.
Most of the firefights were combatants in one wood line shooting at combatants in another wood line. I too liked to get as low as possible but I eliminated the use of the bipod and rested the gun on its pistol grip. The gun was level and fired about 6 inches above the ground instead of 3-6 feet,(depend on the range) of the same gun using the bipods.
After my tour in the RA, I joined the Alaska NG, we had 5 BN, three of which were Alaskan Natives. They were issued MGs but had little real training of their use. I was selected to do a series of Machine Gun schools.
During this period based on experiences from Vietnam (we always train for the next war with the tactics we used in the last war), most Machine gun training was using the '60 as a SAW and not a medium Machine gun. I found very few people (even combat infantry vets) who understood the T&E Mech. and use of the Tri-Pod. You asked some one about MILs and they eyes glassed over.
I bet today you'll find the same thing about MG'ers in the rifle companies now.
Anyway, I divided the MG schools into two sections, the Med Machine gun and the SAW. If property trained then both aspects of Machine gun use can cover both the tactics of WWI and WWII and everything in between.
MGs are great in the assault, but they are quite useful in covering the assault troops from a fix position, much like snipers were used in Iraq.
Its an art, it requires knowing the trajectory of the MG rounds to determine safe zones. I wrote a paper about this a while back, it the latest version is floating around the internet (and magazines) now.
When the SAWs we have now first came out, the only ammo we had was the M193, or that's all we had when we first started getting the SAWs in the AK NG, but now they have better ammo witch extends the range and effectiveness of the system. I believe replacing he 62 gr. Ball with the 77 Gr. bullets would inprove it much more, but we'll see what the future brings.
I learned in Vietnam that the lighter the ammo, the more you carry, the more you carry the more firepower you put out, and that's what infantry is about now, Firepower.
Machines guns have many uses, but one gun doesn't always fit every occasion. The biggest problem with Machine Guns is there is no real training.
When was the last time someone taught Indirect fire with a Machine Gun in infantry schools?