Somewhere on the Trois Monts traverse, every client asks the same question, usually with their eyes: why are we tied together with four metres of rope, and how exactly does that help anybody? It is a fair question. Handled badly, a short rope is simply a way for two people to fall instead of one. This note is the long answer, typed once so I can stop giving it at 4,300 metres in a wind.

Moving together means the guide carries the spare rope in coils and keeps the last few metres to the client just tensioned — four to six metres, no slack, no ceremony. The point is time. A slip caught in its first half-second is a stumble; the same slip given two metres of loose rope is a load no hand can hold. The short rope does not arrest falls. It prevents them from becoming falls at all.

On E-04 the rule is plain. On the ridges above the Col du Midi, on the shoulder of Mont Blanc du Tacul, on the Mur de la Côte, we move together. Where the ground steepens past what a braced guide can hold by hand and stance, we stop, build an anchor, and pitch it properly. The judgement of where that line falls is, bluntly, what you are paying for.

Your side of the contract is rhythm. Walk at the pace set, place your feet where feet have been placed, and never — this is the one absolute — never stop dead without a word. A client who halts to photograph the Grandes Jorasses mid-slope transfers their bodyweight to my hand without notice. Say the word stop, then stop. The view will wait; it has been there some time.

It is an asymmetric arrangement and we do not pretend otherwise. One person is guarding another, continuously, for hours. That is why the ratio on this route is one guide to two climbers and will not be stretched — a third body on the rope does not add a third of the risk, it multiplies all of it.

We practise all of this on day two, on the dry glacier below the Mer de Glace, where a slip costs nothing but dignity. By summit day the rope should feel less like equipment and more like grammar — the thing that lets two people move as one sentence. That is the whole technique. The rest is footwork.