I don't track between songs, too much hassle and inaccuracy. Some typical scenarios I use it for-
Start recording before the performers enter... wait... wait... 20 minutes later the lights dim [hit file split]
End of set 1.. applause dies [hit file split] roll during intermission so as not to miss the start of set 2, just before set 2 starts [hit file split] or not. No missed intros, delete the intermission later.. or not.
IME, file split serves 3 purposes- 1) Easy way to eliminate the chaff 2) Easy way to manage where the file size based autosplit happens (not the end of the world if it splits mid-set since it's seamless but it would be nice to have each set as a single file. 3) Starts a new file which means the last one is somewhat safer with an intact file header if something happens like the batteries failing.