Various short descriptions for 1 product

[brakoops]

I have the following issue. My client has a regular product (let's just call it product A) in category A which is also an alternative for a different product in category Z

As I don't want seperate sku's I have the same product listed in category A and Z. That's easily made possible by Magento...

But then it get's complicated. The client would like to see a mention of Product A being an alternative, but have this mentioned only when selecting this product in category Z!

As I don't find that unreasonable, I was wondering, has someone encountered this before and if so, what have you done?

[brakoops]

as it is, I am thinking about a code like this:

<?php if($category->getId()==your id): ?>
            <?php echo $this->__('some nice text to have the customer understand what's what'); ?>
            <?php endif; ?>

I am baffled it's not possible to add this in short description directly. There's probably a simple solution but I'm not seeing it...

[brakoops]

Getting a bit further, the idea is now to add a static block which calls upon a phtml file which contains the aforementioned code.

The static block is positioned in the right column. The block works - tested with a simple text.

within the static block I have written the link to the phtml:

{{block type='core/template' template='page/html/alt_product.phtml'}}

however, this results in a blank page...