Ireland is an example of this: for there to be a quorum in either house, at least twenty members have to be present. This means at least 1/3 of the Seanad (upper house, 60 seats) or 12% of the Dáil (lower house, 166 seats) must be present for either to form a quorum. That's not written in the constitution, but a standing order of the Oireachtas (parliament).
Even if France has no such requirement in its constitution, it's ridiculous that there isn't at least a parliamentary rule of order requiring it.
The movement M6R's got ~85K signatures, and a grass-roots assembly with ~180 members, transparent auto-financing, but it still need to get much bigger in order to make the change of constitution the big main issue in the next presidential race in 2017. After 2017 I don't know, but changing the constitution, getting back democracy has to be in "every mouth" from now on.
French political life is characterized by a complete lack of impetus for change.