Hi,
The MGA (Minimum Grid Altitude) in that sector is 16400 ft according to the LIDO charts. At the latest above Switzerland, the chaps in their 757's or whatever they might be flying should have reached FL160 depending on the day's QNH. Sometimes when the weather is CAVOK, we simply turn left and head north ASAP traffic/ATC/MIL permitting. Mt. Rosa near Zermatt is 4634 m high. So flying at FL160 you should cross this specific peak by more or less 2000 ft. But the quicker one get's to cruising level the better. But the route structure will not be taking one over this peak (just an e.g.)
Kind Regards