A small amount of communication between the hot and cold wallets is not too much to ask, especially as anyone using SNICKER with a watching-only wallet must regularly interact with their cold wallet to sign the coinjoins. However, this description only considers the initial setup of a watch-only wallet. There are various uses for watch-only wallets, which may not involve offline signing. For instance, a user with a hot wallet on their laptop with xprv may want to watch their addresses using an xpub from their mobile. Alternatively, they may give an xpub to an accountant or their Electrum Personal Server. Nonetheless, these use cases require ongoing address discovery, which would break without SNICKER's functionality.