hum, you are right, according to the [american style](http://blog.apastyle.org/apastyle/2013/03/punctuation-junction-periods-and-parentheses.html) full sentences with periods within the parentheses seem to be allowed. I am not sure if it's my memory failing me or a different punctuation style in french, but I remembered that parentheses are just for fragments, so no period in there. What you learned in school is right anyway, sorry for messing up with it ;)