One thing to note with these things ::

Its easy to do this

<table>
<tr><td></td></tr>
<tr>
<# MyHelper(.......) >
</tr>
</table>

Myhelper(){
return "<td>hello</td>
}

which works at runtime but will play havoc with the VS designer. It will
probbaly fill in the missing  bits and add a TBODY and all sorts, and be a real
pain.
So make sure what's in the designer is valid html, even if that means outputting
more from the helper function.

<table>
<tr><td></td></tr>
<# MyHelper(.......) >
</table>


Myhelper(){
return "<tr><td>hello</td></tr>"
}

as if you didn't know already.