I rode with a club like the OP described in the mid 70's, always supposed to be no drop rides and no rider left behind. I even did a year as the road captain for them. After some turn over of members changed the tone of the club and they left my wife and I behind to fend for ourselves when she passed out from heat prostration on a very busy highway we left them and pretty much stopped riding for quite a while and ran road races (simply looked back at us on the side of the road and peddled away, said they weren't paying attention and left the parking lot at the finish when they got back in, did not ever check on us.)

The club I am in now, West Florida Wheelmen, has two groups in the rides and the "B" group is always no rider left behind. They make it clear that the "A" group is fast paced and keeps going when someone is dropped, so make your decision carefully. the "A" group are fast, skilled and very experienced bicyclist. This is upfront and on the emails sent out each week and the calender on the website make things clear, also. The other group is captained by an senior, skilled rider and if someone falls off a rider goes back to them. they are gotten back to the home base regardless. Our shop rides on Saturdays are broken down into skill level groups and if a rider is in over their head they will be steered to a more suitable group. These small details keep people from getting in too far over their skill level and keeps them coming back. I am still not able to keep the speed level for group rides as I manage things I have to deal with so they keep track of my riding solo with a skilled rider I know and see professionally so he is up on m y abilities. All off the radar but very encouraging to me.

Sorry for the length, I just have had a really bad experience with being lest stranded those years ago and worried about taking care of my wife. The club and shops now are so much better that I really support them as I am able.

Bill