I think this only applies to when you specify the field type IE: $('.classname type') vs $('.classname'). That is why he found that it worked for fields he did not reference as an input type.  This is because when you submit a form, first, every field is deleted from the form and the value is copied to a replacement field of type DIV. I am pretty sure we left out the type but will check when I am back in.

If that (or any other related posts) don't work for you, please start a new post with the second question. It will be much easier for others to search for and better practice to keep each post one topic.