gistfile1.php

<?php
$topListings = array();
$bottomListings = array();

for ( $i = 0; $i < count( $loop->posts ); $i++ ) {
    if ( str_word_count( $loop->posts[$i]->post_content ) >= 30 ) {
        array_push( $topListings, $loop->posts[$i] );
    } else {
        array_push( $bottomListings, $loop->posts[$i] );                  
    }
}

shuffle( $topListings );
shuffle( $bottomListings );

$loop->posts = array();
$loop->posts = array_merge( $topListings, $bottomListings );
?>