I know that a PUBLISHED doc does not require login, but when I read this setting it makes me think the user may still be prompted to log in, or worse, may be forced to login at some point (even if this setting is OFF):
@joost_mineur is right. When this setting is on, a visitor might be presented with a login prompt and if it’s their first visit and they sign up, it’s attributed to you as an affiliate. If this setting is off, no prompt is presented.
When they might see a prompt is if the doc is in “Edit” mode and they go to edit the doc, there will be a prompt asking if they want to edit as anonymous or as themselves. They will also have to be logged in to edit the doc.
If a doc is in “Play” mode, they can play in the doc with no login prompt and changes are not saved. This is great for people to explore Coda features or for things like online calculators where they can find solutions but the data doesn’t need to be stored.