EDIT: OK, I get it. Even a "cold" wallet has to be brought "online" at some point, in order to transfer funds. So, it is a rather ambiguous term.
yep that's pretty much it....you have to bring the DASH wallet online to start the node, but otherwise it's 'cold'. Hopefully there will be a feature in the future where you can sign the 'start-node' command on an offline host and then start on an online host that doesn't contain the private keys, like how you can sign transactions offline in BTC wallets such as Armory.