Former military here…I only ever did this a few times in very specific circumstances. I wasn’t infantry but when exercising that role I did do this a couple of times when on sentry for a long time or when in an OP (observation post). This was rare and only on exercise, I never needed to do it ‘for real’.
The reason I did it is whilst lying down or in very confined/concealed area it’s easier to turn your wrist to see the time, which passes amazingly slowly in these situations. If you imagine you arm outstretched in front of you it’s a lot easier to see the watch face if it’s on the inside of the wrist as you have to turn your arm much less.
I’m not sure I am explaining it adequately, but it these circumstances it’s definitely easier.
At all other times and in my normal role I never did this.
Regarding light discipline, many brands make military versions that are much harder to accidentally press the backlight or in modern tomes allow you to turn off the heartrate monitor lights. Also, we would generally wear long sleeves which would cover a watch in most situations anyway, even in hot climates. There was a gradual mover to 3/4 length or turned up sleeves during my time, when watches would then often then get covered by tactical gloves or sometimes even dedicated covers made to conceal a watch.
The reason I did it is whilst lying down or in very confined/concealed area it’s easier to turn your wrist to see the time, which passes amazingly slowly in these situations. If you imagine you arm outstretched in front of you it’s a lot easier to see the watch face if it’s on the inside of the wrist as you have to turn your arm much less.
I’m not sure I am explaining it adequately, but it these circumstances it’s definitely easier.
At all other times and in my normal role I never did this.
Regarding light discipline, many brands make military versions that are much harder to accidentally press the backlight or in modern tomes allow you to turn off the heartrate monitor lights. Also, we would generally wear long sleeves which would cover a watch in most situations anyway, even in hot climates. There was a gradual mover to 3/4 length or turned up sleeves during my time, when watches would then often then get covered by tactical gloves or sometimes even dedicated covers made to conceal a watch.