IF you replace with the above code you will remove mainbody totally, but if you change this:
<?php mosMainBody(); ?>
Into this:
<?php
global $mainframe, $option;
$m_menu = $mainframe->get( "menu" );
$m_params = new mosParameters( $m_menu->params );
$m_intro = $m_params->def( "intro", 4 );
$m_leading = $m_params->def( "leading", 1 );
if ( $option != "com_frontpage" || $m_intro || $m_leading) {
?>
<?php mosMainBody(); ?>
<?php } ?>
You still have the mainbody when you gonna show full articles, contact us etc.
Then you can adjust the layout on the Menu>Home button to set intro,column etc to 0 as you do on the JA-Teline.