Ziljoe, from my experience, I can say this: calculating distance traveled based on time (for example, it's assumed that a person at a normal pace walks about 5 km per hour) is only accurate for sports fields. Terrain complicated by natural obstacles and additional loads (like a backpack) reduce speed. As an experiment, moving in an unfamiliar forest is about 3 km/h for a trained person without additional loads, while for an untrained person, it's half that.
Estimating distance traveled is subjective; it's no wonder that hikers later tried using homemade odometers.
Regarding the interval between watch stops, the "Sportivnye" and "Pobeda" watches, according to a 1957 catalog of watches and watch accessories, had a power reserve of at least 34 hours. It's quite possible that the guys wound their watches simultaneously or almost simultaneously, for example, in the morning between getting up and setting out on the trail. Considering the watches are from different manufacturers, plus the tolerances within the GOST standard, a difference of 24 minutes and 36 seconds is insignificant. Also, don't forget that on a mechanical watch, 8:00 a.m. could be 8:00 a.m., just as it could be 8:00 p.m., meaning the difference could be as much as 12 hours, 24 minutes, and 36 seconds, rather than 24 minutes and 36 seconds.
As for orientation, the remnants were used as landmarks. If visibility is zero, then climbing is pointless—you could miss the exit point by several hundred meters, even though you felt like you were heading in the right direction.
If you're interested, I can share some books on tourism from those years. They're in Russian, though.
Javier, in the USSR some watches had a dial with a luminous coating.