Shotwell says the Company will attempt to land the Falcon 9 on land, although no time and place are stated. The hope is that the added stability of landing on ground would allow a safe landing.
Just purely the boat moving, even in a low sea state, it’s hard to imagine that vehicle is going to stay vertical. That vehicle is big and tall, compared to the itty-bity-greater-than-a-football-field-size ship.
On risks of ground return:
The risk of damage to the public of ascent is far greater than return. There’s a lot of propellant going up, and there’s very little propellant coming back.
She also notes that there is a flight termination system in place:
It’s a lot harder to think about blowing up that rocket when you’re going up and it has a payload on board. But when it’s coming back, if things look wonky, blow it up.