Yes, that is exactly what I wanted to achieve.
I added echo substr( $this->product->product_desc, 0, 15); to default.php
Code from line 116 looks like...
<?php // Product Title ?>
<h1><?php echo $this->product->product_name ?></h1>
<?php // Product Title END ?>
<?php // Pack Size END ?>
echo substr( $this->product->product_desc, 0, 15);
<?php // afterDisplayTitle Event
echo $this->product->event->afterDisplayTitle ?>
<?php // Product Edit Link
echo $this->edit_link;
// Product Edit Link END ?>
Unfortunately, this only results in the actual code echo substr( $this->product->product_desc, 0, 15); being displayed on the product page rather than the short description.
Please help!