Originally Posted by
Koyote
On our group ride one night, the pack had broken up on our way back into town. Another person and I were riding along, side-by-side, going into the sun. We were chatting as we cruised along at about 22mph. At one point, we rode right by some chunk of debris in the road - we didn't see it due to the sunlight, but we just happened to pass by, one of us on either side of this fist-sized piece of broken tarmac. We just lucked out. Then, from behind us, we heard a loud "pop," then a moment of silence, then the terrible sound of man and machine hitting and tumbling along the pavement. We had no idea that we were being drafted, much less that he was riding behind and in-between us.
Even if we'd known he was back there, I'm not sure that I could've pointed out that debris in time. But I didn't even know he was there. Poor guy: it was his very first ride on a new high-end bike, which got a bit banged up. 'Course, he also got to ride in a helicopter that night, so that was kind of exciting.
The group rides I do are fairly large, so I guess I'm used to random people hopping on. We might roll out with 25-30 and the group will grow to 40-50 by the time we turn around, then shed riders on the way back.
I've been in the situation you describe many times and often end up in smaller random groups heading back into town. Half the time the people we end up riding in with weren't even on the original ride and I never know how many riders are behind me unless I check over my shoulder.
It's fine, I've never thought any of that was a problem in the context of road group rides.