yes, Sue dt
There's a girl at my local session who can only be heard by bats (and fast ones at that), and after cajoling by me eventually sang it an octave or some large chunk of one lower... and slower. I explained that the notes were now more discernable and held better... the song became more melodious and pleasing to the ear as a result. We all try to get our songs over too quickly when unsure, and I find I sometimes start in the wrong key when trying to 'punch out' over the ambient noise. The Confidence to relax and start lower and slower only comes with practice in friendly sessions.