LeMay obviously had McNamara's ear when he rushed the M16 into production for Viet Nam with disastrous results. The Whiz Kid took the advice from an "Expert" and came up with a "better idea" about what makes a superior infantry rifle. Like the article says, the M16 killed a lot of GIs when it jammed / seized up in combat. Since then, it's been one band-aid after another to try to fix it's numerous short-comings. It has to be the only rifle in history fitted with a device (the forward assist) specifically designed to try to deal with the many anticipated jams when the rifle decides to crap out at the worst possible moment.
The AR still today has the same basic flaws with the DI system and the anemic 5.56 round. The work around is all the design bandaids, barrel/rifling and bullet changes and constant maintenance and even then it's not enough.
Like I alluded to in an earlier post, when the M4 started getting it's butt kicked by other (piston) rifles in head to head competition, the US military stopped the trials. Apparently, a jam every 400 rounds is an "acceptable" failure rate for the M4. That's a disgrace and a great disservice to our troops.
Who knows what private discussions were had. AFAIK, the General was concerned about his service and I think it's unfair to assign blame to him when so many more powerful people were responsible for military-wide adoption...
The DI system, though not ideal for extreme neglect or infrequent cleanings in field conditions, is adequate for most uses. For instance, the standard combat load for US GIs is 210 rounds.
Under sustained high rates of fire or engagements where 1000 rounds are going through the weapon, yes DIs are less than ideal. But as noted, the carbine is typically considered a secondary weapon to other forms of firepower...
In total agreement that the launch of the AR15 in VN was a boondoggle. I also agree that the 5.56 round is not ideal for shooting into cover, including dense jungle, where bullets are more likely to deflect off course than penetrate through... Further, the DI M16 also really wasn't ideal in rifle configuration (20" barrel versions w/ fixed stocks) nor was it well suited for the high rates of fire, mad minute/cover shooting/etc reactions to conflict where at least a few mags were dumped on full auto with that light profile barrel, minimal chrome in the action vs what Colt/Armalite recommended, improper cleaning instructions, and reusing mags that were designed to be disposable...
A perhaps good part about DI guns under severe use is typically the gas tube will burst before the barrel under severe heat, rending the weapon single shot but functional (at that point the barrel is likely on its last legs due to losing temper) but still serviceable.
The CZ805 bren had a 2 shot burst setting (auto resets unlike rachet system M16 burst) on it -- with the issues w/ a 5.56 round, I think that makes a tremendous amount of sense, and that's before you look at increased hit probabilities as it relates to both sight acquisition timing, time lead down range, and shooter aiming/estimation errors...
So I'm with you on 5.56.
However, I am totally on board of this read about 6.8spc not being tremendously different from 70+ gr 5.56 loadings:
http://www.thefirearmblog.com/blog/2015/04/04/not-so-special-a-critical-view-of-the-6-8mm-spc/ I do think you need to up power beyond 6.8 spc and 7.62x39 before you reach an ideal do everything intermediate round.
And I generally agree for the need of the military to adopt new small arms (and surplus -- not destroy per usual -- their current inventory of weapon and mags). Why? B/c the primary cause of failure for the M4 carbine, Beretta M9 pistols, and most small arms is all the wear and tear and defective mags, etc, that the military continues to keep in circulation/use. Any weapon system if starting with fresh builds, mags, and parts would be more reliable than the current military inventory.
Are there better weapon systems than the M4 -- in my opinion yes. But it's based upon my personal needs/assessments. Everyone's perspective on what is important differs. Currently the military is driven by social justice concerns so small arms will have to be able to be used effectively from 5' 110 lb petite females to 225 lb 6'+ linebacker build types in special operations community... Considering that, the M4 continues to be superior in many respects to other offerings. However, the M4 w/ a piston kit (which most in that military trial were) is not typically more reliable than weapons designed around a piston system from the start. But typically they have a notably different manual of arms, are heavier (unless lots of polymer), and many use the same mags (so doesn't fix the bad mags in circulation issue -- remembering that mags are responsible for 4 out of 5+ malfunctions w/ M4s in the field)...
One thing I didn't note earlier and probably should have is that some piston systems like Adams do effectively free float the piston inside of the gas block, which helps with accuracy but doesn't totally resolve. 1/2 to 3/4 MOA requirement -- DI wins. 1 1/2 MOA requirement both DI and piston guns are equally competitive. Most soldiers probably aren't 1/2 MOA shooters, especially with iron sights or 2+ MOA red dots, so take that into consideration too...