Really nice route. A lot of mixted climb, some short passages with pure ice that day. We climbed only the Triangle of Tacul, without going to the very top of MB du Tacul.
The main issue was the descent. The risk of avalanches - especially on the NW face of MB du Tacul - was considerable. After one of our ropes broke, we needed to rappel down all along the western ridge of the Triangle. A long day... But successfull.
The night before it was snowing at the Cosmiques but at the time of our start at 4:15 AM from the Refuge (with my son Christoph and our guide Eric) the sky was clear and for the rest of the day, absolutely perfect weather and snow conditions. We did not encounter a single party for the entire ascent route but there were lots of climbers on the normal PD route back to the Cosmiques. Quite a bit of exposure on some of hard snow/ice pitches. A memorable climb!