True, and if you"re about to edit a song with low BPM yourself it"s wise to increase the BPM. As mamba99 says, it makes it easier to get the length of the words/syllables just about right. I.e. not too long or too short. But you don"t have to think that much about the BPM yourself before editing if you"re using Ultrastar Manager and run the task of "Increase low BPM values". Ultrastar Manger will then double or quadruple your BPM and all of the timings/time stamps accordingly in your song datafile.
Pheeef The original BPM of this song is 96. But you can work on a TXT file better when you have more space for the length of the vocal pitches because sometimes a singer changes the pitch very often during a short time. So if you"re looking to other TXT files here you will find a lot of songs where the BPM value is doubled or quadrupled. But that doesn"t have a negative impact on the song performance in UltraStar Deluxe, rather, it helps.