Hello Guillaume,
because I'm a woman I can say "that's what I meant anyway". 
No, I guess you're right. I was always wondering why my rating was never shown, but that was to the fact, that I always use the comment-function instead of that link I just found because you let me to it. And I thought it was because most of the time I rated after commenting or commented later after rating. ^^ Thank you for that, again I learned something on SCN. 
Nonetheless, my key-statement is the same. IMO the star-rating isn't meant to be anonymous. It's just a broader way of showing what you think of the content. Like/Nothing is too 1/0.
I'm not sure, but I think there was also a discussion if there shouldn't be more information with the star-rating. Like which were exactly given to come to the average one etc. But maybe I'm mistaken.
Regards,
Steffi.