Here's a question

[Suhiir]

Well...I am technically a Nam vet (was a paper shuffler in supply at the time), never left Da Nang except to visit Saigon a couple times.

As to what I think...

Personal opinion !!!!!!!

The USMC learned to deal with gurellia/counter insurgency situation during the "Banana Wars" in the Caribbean during the 1930's. In about 1965 they were implementing their "Combined Action" program. Units made up of both US Marines and Popular Force (PF) personnel. The primary mission of Combined Action (CA) organization is local defense. In this connection, the PF members of the CA unit contribute to the combined effort by their knowledge of the local area, people, customs, government and Viet Cong activities. Marines contribute to the combined effort by training the PF and increasing the PF's combat effectiveness; in artillery, air strikes, or reinforcements if required. Marine personnel are assigned to these units on a semi-permanent basis to permit sustained operations in the a certain area and continued association with a particular group of people.

It was working...

The U.S. Army Army intended to fight an attrition war...attrite insurgent forces faster than the enemy could replace them.

Well, we won nearly every battle, the daily KIA count was on the nightly news, we still lost the war.
Why?
Because Mao, unlike the US Army, understood the battle was for "hearts and minds" not real estate or kill counts.

Vietnam was also used (a LOT) to test and refine weapons (M16's), systems (attack helos), organizations (infantry vs mech unit TO&E), tactics, methods (logistics handling, medivac, etc.).

WinSPMBT is an excellent simulation (more-or-less) of tactical combat. There were a zillion different combination's of weapons-organization-systems that "need" to be included in the game to be able to represent tactical combat in Vietnam.
Pyros is doing so.
And doing a damn good job of it.