To expect a firearm of that design to be able to generate sustained fire is ridiculous.
It was a procurement desk officer 'solution', and doctrine was revised (for which you may read 'bent outta shape') to accommodate it.
That the weapon subsequently received the neglect and disrespect sketched on here indicates how little the doctrine was believed.
The whole story is symptomatic of an Army whose infantry arm had grown (and remains to this day, IMHO) profoundly ignorant of, and thoroughly complacent about, the nature and effective employment of its most basic toolset.
That ignorance and complacency has not been shifted one iota by the experience of TELIC and HERRICK, or so it would seem.