Any way to turn off post cache when a particular bb code is used?

[BirdOPrey5]

I have a BB Code that I modify the exact size of based off a custom user profile field.

I do this by using a hook on bbcode_parse_start, scanning the code for this bb code, and if found setting a custom height.

However while this seemed to work I notice now that the size is usually set by the first person to view it and I guess it's cached. Subsequent viewers don't see it at their specified height but that of whomever viewed it first's height.

This isn't an often used bb code so i figured disabling the post cache if this bb code was used wouldn't be a big deal.

However I'm not seeing how to do this... the code in class_bbcode.php to test if it is cachable is:

if ($this->options['cachable'])

So I tried just setting $this->options['cachable'] = false, but it doesn't seem to do anything at all.

Would there be some other way of turning off the post cache for a specific post?