Leadfingers wrote: The problem is that SO Often the words DONT have any thing like the same quality as the tune

That is a risk any songwriter takes, whether with his own tunes or with the tunes of others. And similarly when setting poetry to music.

Tons of texts have been set to tunes which were originally instrumental, and produced terrific songs. Tons of poems have been set to tunes after the fact, and produced terrific songs. We would be greatly impoverished if this practice did not occur. Granted, mountains of mediocre or abysmal songs have been produced by the same process, but the songs which don't measure up tend to die away when others give them a tepid reception. Numerous such efforts are necessary if people are to produce the occasional gems.

The only real errors occur when performers are so in love with everything they produce (or are so pushed by recording contracts) that they lose their ability to discern the potentially good from the merely derivative, and mostly sing the latter. On the other hand, think of how many best-loved songs were issued as B-sides, the A-sides now forgotten.

In any case, "authorized" is a useful distinction, since you may run into legal woes with a version that isn't. So don't be dissuaded by knee-jerk purists (misconstruing the term) from asking this cogent question.