Agree that the sheer size of the group makes this a huge aggravation for anybody following in a car. There likely needs to be some form of club policy limiting a group size to 12-15. I quit riding with one of the local clubs when there were too many what they call "show and go" rides, with no designated leader, just a big unorganized group of 20 riders or so. I witnessed much really poor decisions by people like passing cars stopped at a light on the left side, when everybody, cyclists included, were going straight, unsafe right on reds onto roads without a shoulder, etc. I gave up and now only ride with a small group of 3-4 other people.