generated html is invalid

[dmitry-a-l]

will produce following output:

Namevalue

instead of expected output:

1. Namevalue

[MBO]

That's right. According to docs (and how it works in formtastic, because I created attrtastic to somehow mimic formtastic behavior) you should use:

<% semantic_attributes_for @dossier do |attr| %>
  <% attr.attributes do %>
    <%= attr.attribute :title %>
  <% end %>
<% end %>

It's a bit burdensome to use it like this and your suggestion to simplify it is good. I'll try to implement it in a spare time