Ok, I've wasted enough time trying things, time to ask for an aimed answer:
I would like to have a simple login form (or any form for that matter), and be able to post it, not with a button, but with a link.
So no input, but a.
I've seen plenty of solutions for this type of question, and I've tried lots of different options, and every single time, nothing happens.
I've stripped all the JQuery from what I have, so this is the "base" situation: what's missing to make it submit the form?
<% using (Html.BeginForm("Login", "Account", FormMethod.Post, new { id = "loginForm" }))
{ %>
<%= Html.TextBoxFor(x => x.UserName)%><br/>
<%= Html.TextBoxFor(x => x.Password)%><br/>
<a href="#" id="submit-link" class="button">Log In</a>
<%}%>