As you say, singing all the time is not realistic. But there are approaches that teach you to use your vocal folds in different ways (some of which have some similarity to how the vocal folds move in singing). For example, techniques such as continuous phonation and prolonged speech. This might be of interest: https://psychology.stackexchange.com/questions/10832/why-do-people-who-stutter-have-less-difficulty-singing-than-speaking/10839#10839 There is a new intensive speech therapy programme that teaches you to alter your vocal fold movements in some of the ways outlined in the post above. Have a look at www.mpi2.com