I will agree with you, however the usage of callbacks depends on one's requirements. We do provide the tool, however it cannot work with the browser's back button, not because the callback breaks it, but because the browser does not offer the API for us to catch the button press. We understand the importance of this major shortcoming, but unfortunately it is simply beyond our control.
The same holds true for Flash sites, Microsoft's ATLAS, and all other AJAX frameworks offered on the market (try https://www.beatport.com/default.php
- it uses custom back button in a flash site). There are many discussions on the topic in the internet which offer ways to handle a custom BACK button on the page. We will try to provide such back/forward functionality with the next version of our controls and on our site.
All the best,