I can’t see any seasoned soldier actually patrolling without a bullet chambered.
Anyway, the title is misleading. The weapons have full magazines, they just don’t have a round chambered. The only thing this order does is cause a soldier who actually obeyed it to have a slower reaction time in the event of an ambush and likely get himself killed as a result. That’s all this means.
It also means you give yourself away ‘cuz you can’t silently chamber a round.
The enemy will know you are there, just like chambering a round in your Glock or your pump shotgun.
Chambering a round has a VERY distinctive sound.