Proper Etiquette in this situation

What's the right thing to do in this situation? In general, in the National level group, drafting is a no-no. I really like training with them b/c drafting of any kind is pretty minimal. Either we all go 10 seconds back or if we are going 5 and you catch the person in front of you, you either pass them or they let you go in front of them at the next stop. However, what do you do in this practice situation? You are swimming 2nd in the lane. Boy in front of you starts missing the intervals during the last 25% of the set. He's done a great job of leading the lane until this point. You catch up to him as your entire lane is now missing the intervals (although the rest of the lane was missing the intervals on their own doing anyway). However, you are not sure you can/ should pass him. Should I have tried to pass even though we were at the tail end of the set (and passing would be a heck of a chore as we were all pretty dead)? Stayed on his feet as the set is almost over? Waited another 5 seconds but then having other people on my feet? No one else was really on my feet as we had sort of put some distance between us and the rest of the lane. I sort of feel if the lane leader misses the send offs that it's more of a touch and go/ anything goes/ fend for yourself scenario. Thanks!