flush_rewrite_rules(), add to core for register_post_type function?

I’m sat in the UK WordCamp, on a talk about custom post types.

A debate occurred, and we realised that there’s something that could add a little ease of use, with no downside…

Would it make sense to add to the core code for register_post_type function, so that when the function creates a new post type, it does a flush_rewrite_rules(); at the end?

After creating a new post type, we will always want a flush, but if it only runs when a new type has been created, it won’t run unneccesarily?

Thanks,
Chris