Considered two options on this route. Based on the pictures provided, climbing those rocky hills seemed like it would take too much time, so I tried keeping to trails and flat areas in between. When I looked at the map, I found two options. Starting with the one I didn't ultimately choose, one could go right in a southern direction to the large clearing on the side of the map. I would use that trail until I hit that dark brown patch on the trail's right. There's a trail branching off there that goes past 11 and 12. That trail goes very close to the hill that 3 is on, and I would look out for the big cluster of rocks and head for right above it on the hill.
The other option I saw was going left from control number 2. This allows a very quick and relatively climb-less route to the trail. I would be able to go fast on the trail up to the junction at control nine. I'd use the direction the control was facing and go straight off the trail to hit the other trail by the water stop and the large hill that would be a useful collection feature. There's a flat portion to the right of the hill, which I would run across to get to the next trail. I would follow the trail to the trail junction and climb the hill, aiming for above the large cluster of big rocks, across the spur, and into the control.
On this leg, it seemed like the best option was to use the trails to my advantage. The rocky hills are harder to navigate and slower running, so it seems it would be to my advantage to stay on the trails. Of the three routes provided (Tsvetkov 14:51, 1st; V. Novikov 15:48, 2nd; L. Novikov 16:19, 4th), I took the same route as Valentin Novikov. Both went about the same speed, and the routes started to differ at the trail junction at 17, where Tsvetkov went right. The explanation states that Valentin's route had more climb and was more stony when she was off the path, even if most of her route was on the path. Tsvetkov, when off-path, was running through flat open forest with few stones, and he had less distance and climb than Valentin, which translated into a faster time on the leg. I hadn't considered the route Tsvetkov had taken, but looking at it, the marsh approaching control 3 would have been very fast running, and there's a small trail I didn't see between two large trails that would have allowed a runner to be faster than I initially thought.