What happens if you specify the name of a sheet that already exist

This document needs to describe the integration step where you pick a folder and a spreadsheet name. It needs to explain what happens if you specify the name of a folder or a sub-folder that already exists, and what happens if you specify the name of a sheet that already exists in the folder (or sub-folder) that you named.

That would be very helpful, and hopefully would cut down on the questions you have to answer!

Everytime you add google sheet integration on your form, it will create a new unique Google sheet in your google docs account. So having an existing google sheet name or sub folder will not matter. 

The new google sheet generated during the google sheet integration process is system generated. 

The key here is that the generated submission google sheet generated will always be new.