I am trying to iterate through form.fields in a template and for:
{% for field in form.fields %}
{{ field }},
{% endfor %}
I am getting
You want to iterate over "form," not "form.fields". The latter returns Field instances, the former returns BoundField instances (even in the case of an unbound form), which render their widget HTML.
form.visible_fields and form.hidden_fields are utility methods to only get the visible/hidden fields of the form, but they also return BoundField instances. They are not in any way parallel to form.fields (I agree that this isn't the clearest possible API).