About 12 years ago I ran in a local 5K.  I'm slow so I lined up in the back of the pack.  There were a few women who lined up in the front.  Don't know if they were just close together or were holding hands but when the starter yelled "Go" and the faster runners took off there was a domino effect fall blocking most of the start of the race.  Runners were trying to get around the confusion on the sidewalk and dogding in and out.  Luckily no one was hurt but there were a lot of very angry and very sore runners and I can't blame them at all.  What were those people thinking?  IMO runners with jogging strollers or dogs on long leashes should start to one side of their pace group or in the back of the pack and walkers (not run/walkers) either start at the back of the pack or have a delayed start exclusively for them.

Women's Only 5K, which had over 3000 participants and it was my first race.

They lined people up by their time for a mile. Since it was my first race, I was in the section for 14+ minute mile.

Of course they let the faster time groups go first. Once they told us to go, they meshed us with the huge group of walkers. There was absolutely no way I could start running for about 10 minutes.

Luckily it was my first race and I had no time to compare to. If it wasn't I may have been a bit peeved because there would have been no way to be accurate that way. Next year when I do it I'll definitely be in the faster runner line

I had the opposite problem.

Last year at the White Rock Marathon in Dallas it was so crowded that there was no possible way (post portapot visit) I could get to the back of the area where my run time (10-10:30) was lined up.  In fact, police were not letting anyone else behind the barriers even 20 minutes before the race because it was just so crowded.  They told the rest of us latecomers--and that was a heckuva lot of people--to just start at one of the three crowed barricade entrances near the front and blend into the other runners.

Well, that was a mistake.  Because of the crush of people behind me--runners and spectators both-- I couldn't just stand still and wait until my race time group loped by after the gun went off, or I would have been trampled to death.  So I was literally shoved into the race at around the 7 minute mile runner group.

I immediately dodged and weaved my way to one side but I felt terrible about being there and being in people's way.  No way to get on the sidewalk either as they had the sidewalk barricaded for crowds the first half mile.

So sometimes us slower runners aren't up front on purpose...and I apologize to anyone who had to run around me that day.

PS I did have a PR that day and it was probably because I ran that first mile as fast as I could to get out of the way!

Terry