Indeed that is correct. The problem that I had described probably will almost never occur I assume.
I am not sure if that is correct... I "think" that cloning of messages might be a new kind of hook, but I may be completely wrong!!!! The message hooks have been introduced via this pull request. But as you can see here it is not decided at the time being how/if custom cloning would fit into this picture...
BTW you can read here that cloning happens between the preRoute and onSend hook.
I try to avoid mentioning @knolleary as much as possible, but I'm afraid he is about the only one that can judge whether you are heading in the right direction...
