I firmly believe that Telephone trading is something that belongs to the past. Personally, I would use such option only in case of emergency. I strictly speak from the perspective of a retail trader.
Yes, but emergencies can come more often than one might expect. I witnessed two power outages in German cities in the past few years and I don't even live there anymore It's something you wouldn't expect in the first world but in the end all it takes is a failure at one electrical substation and you're sitting in the dark while the phone network is relatively robust, at least more robust than internet (including mobile internet, hint: a UPS at your celltower might not be enough!).