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Where does the time go? In "link_to"

For a table with 9400 records:

The following code, all Ruby On Rails-ed up, takes 8.15s
<table>
<tr>
<% for column in Journalabbr.content_columns %>
<th align="left"><%= column.human_name %></th>
<% end %>
</tr>

<% for journalabbr in @journalabbrs %>
<tr>
<% for column in Journalabbr.content_columns %>
<td><%=h journalabbr.send(column.name) %></td>
<% end %>
<td><%= link_to 'Show', :action => 'show', :id => journalabbr %></td>
<td><%= link_to 'Edit', :action => 'edit', :id => journalabbr %></td>
<td><%= link_to 'Destroy', { :action => 'destroy', :id => journalabbr }, :confirm => 'Are you sure?' %></td>
</tr>
<% end %>
</table>

By removing content_columns and send_columns and explicitly stating what columns to print, and keeping the same output, the code takes 7.86s.
<table>
<tr>
<th>Full Journal name</th>
<th>Journal name abbr.</th>
</tr>

<% for journalabbr in @journalabbrs %>
<tr>
<td><%=h journalabbr.full_name %></td>
<td><%=h journalabbr.abbr %></td>
<td><%= link_to 'Show', :action => 'show', :id => journalabbr %></td>
<td><%= link_to 'Edit', :action => 'edit', :id => journalabbr %></td>
<td><%= link_to 'Destroy', { :action => 'destroy', :id => journalabbr }, :confirm => 'Are you sure?' %></td>
</tr>
<% end %>
</table>

Removing all erb takes 0.46s.
<table>
<tr>
<th>Full Journal name</th>
<th>Journal name abbr.</th>
</tr>

<% for journalabbr in @journalabbrs %>
<tr>
<td><%=h journalabbr.full_name %></td>
<td><%=h journalabbr.abbr %></td>
</tr>
<% end %>
</table>
Now, removing all link_tos and replacing them with explicit HTML and javascript, with the same functionality as the first code, takes 0.655s! Just as neat and much faster!
<table>
<tr>
  <th>Full Journal name</th>
  <th>Journal name abbr.</th>
</tr>

<% for journalabbr in @journalabbrs %>
<tr>
  <td><%=h journalabbr.full_name %></td>
  <td><%=h journalabbr.abbr %></td>
  <td><a href='/journalabbr/show/<%= journalabbr.id %>'>Show</a></td>
  <td><a href='/journalabbr/edit/<%= journalabbr.id %>'>Edit</a></td>
  <td><a href='/journalabbr/destroy/<%= journalabbr.id %>' onclick="return confirm('Are you sure?');">Destroy</a></td>
</tr>
<% end %>
</table>
Cool code HTML escaping and highlighting from palfrader.org
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