Fitz Roy was in cloud for four of our six days. That is the number worth writing down before the pretty photos, because it is the number that governs the whole trip: this traverse runs on weather windows, not itineraries.
We covered the 88.5 km circuit in six days against the trail’s 5–7 day range, with 4,250 m of accumulated gain — most of it in short, brutal pitches rather than one long climb. The Torre Valley approach was the calm day; the col crossing toward Piedra del Fraile was the one where the Patagonian wind actually earned its reputation, gusting hard enough that we dropped and waited it out rather than push across an exposed section.
What we would change
Build in two spare days beyond the stated 5–7, not as a buffer for pace but as a buffer for wind. We had one clear dawn at the Fitz Roy lookout in six mornings, and it was worth every hour spent stormbound in the tent waiting for it.