...but NOT with wOS devices. Apple is crystal clear about this. The only way to pass any data into the
Watch is through there iPhone's
Watch master App.
The
Watch has no way of connecting onto your WiFi network.
Where are they clear about this? It's seems like assumption to me.
Don't get me wrong, I understand there will be major dependence on the iPhone, but communication will not be locked between the two to enable things like Handoff between it and OS X. There's no reason to use iPhone as a buffer in cases like that.
The Watch's Wifi capabilities haven't been explicitly told to anyone, yet. The SDK devs themselves haven't offered any specific evidence other than, "you shouldn't anticipate how data is transferred to the device." With that said, I would be surprised if Watch
required you to put music on your phone and then transfer it to your watch each and every time you wanted to update. Assuming Watch's Wifi antenna is used solely for BT high speed, iPhone can add it to the network via Bonjour protocol which seems much easier and straight forward, plus pushes the device ever so slowly towards independence.
Edit: Though, after seeing the companion app, you may be right. It might have to go iTunes -> iPhone -> Watch