Group training and your performance is always an interesting topic to bring up, especially considering people get so passionate about it. Don’t get me wrong, so was I for years. See the thing about training in a group is that the workout and/or the workout intensity is not specifically designed for you and where your performance is actually at.
Instead of progressively overloading at your own current level of performance, the group environment will typically “motivate” you to workout harder. Many people believe group training to be a good thing for results, however this thought pattern and modality towards your training could be the exact reason you are staying as the under dog (most unfit in your group).
Are you the person at the back of that pack thinking because you have the most room to improve you will be better by hanging out and training with people whom push you to your limits..?