I found myself on a ride similar to that one last Saturday. I hung in with the fast group for 13 of the 27 miles. When I did get dropped from the fast group the slower group was too far behind for me to even regroup with them. I ended up doing th rest of the ride chasing the fast group. I will be doing the same ride this weekend. One day I will be able to hang in for the entire ride. I ride solo during the week so 1 extremely hard workout per week will not kill me (Hopefully).