First, understand what the switch knot is. It is an essential knot in many situations, but it also has a potential risk, as explained in this video.
In the video, the ascent is to the left.
Until the 2-second mark, the switch (the 15 cm section between the harness and the rope) is facing downhill. This is the ideal case because if I slip, the guide stops me immediately. I don’t have time to gain speed.
At the 7-second mark, the switch is facing uphill, and this is where the risk appears: if I slip, the guide can only brake me after the switch flips back downhill. This happens only after I slide 15 cm × 2 = 30 cm. The impact might be too strong for the guide to handle.
Take into account the warning from trekking-switzerland.ch/blog!