Hum, it is true. 
I never had to use scripts loaded in the page directly.
I know from documentation that there is an API for Javascript execution, but never had to use it in such a situation (in the load of the page). However, I will have to use it now, in a project I am working on. So, if I have any updates on my attempts to get it working, I will surely post here and share with the community. Just like I did for the very first message in this post.
Hope I can help you soon.
Best regards,
Pedro