I am looking for best practise patterns how to separate static phrases (e.g. button labels, status messages) from the actual template files when developing a custom theme? It is not necessary to make such phrases dynamically accessible as real WP content.
My research lead to the topic of internationalisation (http://codex.wordpress.org/I18n_for_WordPress_Developers). However, to me I18n appears a bit too much of an overhead for my purposes.
I am thinking of a separate phrases file which gets included, say, in header.php (or rather functions.php?). There, phrases would be defined and assigned to variables or constants, which could be used as place-holders in template files.
example file phrases.inc.php
define('SEARCH_BUTTON_TEXT', 'Search'); ... define('FILTER_SUCCESS_MESSAGE', 'Your filter results');