Commercial landlords must have shivered when they heard Twitter’s CEO, Jack Dorsey, tell his employees last month that they could stay working from home indefinitely.  “If our employees are in a role and situation that enables them to work from home and they want to continue to do so forever, we will make that happen”, said Dorsey. “If not, our offices will be their warm and welcoming selves.” Commercial landlords do not like this type of talk. It’s a short hop from “work from home if you want, and if not our offices will be unchanged” to “work from home,…