The editors on our site would like to have a subtitle. So an article can have a fancy catchy title and a subtitle explaining the title. (i.e. Title "I've always liked jazz!" and subtitle "Iggy Pop talks about his new album") In K2 you can create an extra field, but as far as I can see, extra fields are always show below the article text. Is it possible to to create an extra field and have show at an other position in the lay-out of the page, i.e. below the title field?

getk2.org/documentation/tips-a-tricks/display-single-extra-fields-anywhere-in-your-k2-content

Good to know! That's what I'm looking for. 
Two related questions:
- are extra fields limited to the article page itself, or can one show extra fields in the list / blog view as well
- can you do a form override for the article edit form, so that an extra field is on a different position than in the tab with field groups?

getk2.org/documentation/k2class2012/k2-template-and-overrides
getk2.org/documentation/tips-a-tricks/display-single-extra-fields-anywhere-in-your-k2-content

Ah yes I see the extra fields can be shown in the list views as well.

But what about the edit form? Since K2 uses the edit form of the admin. The itemform.php in the template points to /administrator/components/com_k2/views/item/tmpl/default.php
What I want is that when an editor add a new article, the subtitle field should be shown directly below the title field, and not in the extra fields tab..