Reading that article I see no proposed solutions to this sail problem. They mention wind as an issue for delivery times but not safety. There's also no acknowledgement that the "scaling law" that makes building huge airships lucrative also makes these problems worse.
You're failing to see the secret that is exposed by the fact that their Chief Engineer comes from hyperloop. They're going to dig tunnels connecting all their destinations and run the airships underground in a vacuum sealed network. No atmospheric drag at all! Bingo!
I don't particularly defend feasibility of Hyperloop, but did want to point out that your comment sounded awfully like when people were ridiculing the idea of human flight, landing on the moon etc... Finding engineering solutions to what looked as "impossible" challenges were some of the best feats of humanity so far.
Right, I am not saying they're right or wrong (not something I would know anything about), but it seems they've been vaguely aware of the issues from the start. Namely, before the SpaceX engineer and starting the company.
