Sparkchaser I was a kid, I wasn’t going to ask him how but he was one of the top chiefs.
One only needs a single eye to use most transits.
True story, when I was younger I had perfect vision but as i aged I became near sighted in one eye and far sighted in the other.
I have corrective glass’s which make my vision perfect except for one thing looking down at stairs, so to navigate a set of stairs, until I got it worked out I would only use one eye or miss what I perceived the height of the next step down and stumble like a drunk.