Back before I understood that I should make multiple segments on one reservation, I was on the LSL that was 5 hours late into Chicago due to a train/pedestrian fatality. This meant we were a few minutes late to catch the SWC, but they held the train presumably because there were a number of people besides my sister and me that were on the late LSL. I don't know how many, but apparently enough to hold the SWC. I didn't know enough to have requested linked reservations either. Whether there would be enough people catching the Pere Marquette from the SWC for them to do a similar thing, I wouldn't know. The next time I traveled by train, I still didn't realize about having multiple segments on one reservation but found out about that from this forum. I also found out about linking reservations. When I called to have Amtrak customer service (or whatever it's called) link them, I didn't have any problems; I just explained the situation, and the agent seemed happy to oblige my request.