1) Empty fields cause the same effect as a field with a value. An empty text field has an empty string as a value.
2) fields hidden by conditional logic are not submitted and not updated.
3) Not sure.
I have used a mechanism in some recent projects where I have a choice field, like a checkbox or multi-select field where the client chooses which of the settings in the repeater that they want to set (in my case a flex field, but they work the same). The all of the other fields are conditional based on the selections made in this field. This means that anything they don’t want to set is not submitted. But this increases the complexity of coding because I need to check the selected values of these fields to see which of the other fields I need to use and which of them I will substitute in default values.
