achensee on "[Plugin: WordPress SEO by Yoast] extend $replacements array with additional author_meta fields"

Yoast SEO is the best, most flexible and most reliable SEO-Plugin for wordpress. For a project we need to add a (custom) author_meta field to the $replacements array which can be used in the title. Similar to %%cf_<customfield>%% we manually added a few lines code to wpseo_functions.php - unfortunately this will be gone within the next update...
...so my question is, if there is a smarter way to add custom %%shortcodes%% or including custom author meta fields will be added in future?

http://wordpress.org/extend/plugins/wordpress-seo/