We had threads about "folk processing" existing songs by known songwriters. The case of poems by known poets is not essentially different, but there is an important additional point: the stanzas of a regular poem will have identical verse structures, but may differ in their rhetorical stress pattern. (This is particularly marked in French poetry.)

Composers who insist on a key mark of folk songs may find a melody that somewhat fits all stanzas (but none really well).

However, in contexts of modern stage performances, it is quite justified to vary the melody slightly or even radically from stanza to stanza, as classical composers frequently did.

GSS, can you give us examples of what changes have been suggested, and why?