20 minutes is far too long when you have to hurry during a battle.
20 minutes is to adjust from full day light, to night time darkness.
We have the evening in between, for our eyes to begin that adjustment naturally.
Your eyes need to be open to receive the light and adjust to it. Our pupils dilate as it gets darker, to allow more light in.
I do not think people wearing an eye patch are walking about with that eye open, beneath it.
It's not worth losing 50% of your vision for the whole day, just to save 10 mins adjusting to lower light, from evening to nightfall.
No-one in their right mind would consider that to be a productive outcome.
It would be far more productive to simply sit in a dark cabin, with no lights, for 10-20 mins before dusk. Then emerge with
both eyes fully adjusted.
Oh yeah, I'll just put this patch on my right eye and make the whole right side of the ship a blind spot, all day long.
That can't have negative consequences...
Not like they didn't have battles during the day!
What you gain is irrelevant, if what it costs you is a much greater loss.
Hanidcapping yourself, by removing 50% of your vision for 10-14hrs, just to save 10 mins adjustment time, is negative equity, not profit.
So promoting the 10-20 minute gain, whilst not acknowledging the 10-14hr loss, is confirmation bias, at best.
Hence the theory is implausible.
The more plausible theory, is that they used it to prepare for going beneath deck, then switched the patch from one eye, to the other.
The eye that had been beneath the patch was able to adjust to the low light conditions, beneath deck, more quickly.
Then they swapped back when they came back on deck, to daylight again.
But this still seems to be rather minimal gain, for quite consequential loss.
