HTML form tag with no attributes - any reason not to?

Question

At risk of sounding like a fool - The html (html5) designers at our firm keep handing me functional mocks with form tags that have no attributes...

<form>
    <label for="name">Name</label>
    <input type="text" id="name" name="name">
</form>

Every time I see this I lose hope in humanity just a little more. But I don't know if I should round them all up and lecture them on form attributes and why we need them since I can't seem to find any documentation that says they are "required." By default I know the form tag will assume things, like method and action, but I prefer those attributes are in place rather than omitted. It's just how it's always been for those of us who have been writing HTML since it began.

So the general question is - Is there anything wrong (however you wish to define that) with using the form tag with no attributes? If your intended action is the current page and the intended method is get, then what argument is there for including versus excluding the default attributes? Or assigning it an id that you don't use?

I expected to see this:

<form id="search_form" action="" method="get">
    <label for="name">Name</label>
    <input type="text" id="name" name="name">
</form>

Answer 1

It will depend on the DOCTYPE you are validating against. For example in HTML 4.01 Transitional and Strict, the action attribute is required whereas the method attribute is optional.

In HTML 5 both attributes are optional.

Answer 2

The biggest issue with not having an id and action attributes on a form is that if you have more than one form on the page it is very difficult to say which one is being referred to - in either client or server code.

As James Montagne mentions in his answer for HTML 4.01 transitional the action attribute is required.

As a general issue, I personally would always be explicit about the id, action and method - keeps these important attributes in the open and makes the point that they were not forgotten.