I wouldn't recommend learning the song 'The Limerick Rake' in that case, MudGuard, for such reasons as you outline above:

"If I chance for to go to the market of Croom
With me cock in me hand, and me pipes in full tune.
I am welcomed at once and brought up to a room,
Where Bacchus is sportin' with Venus...."

Some of them you do have to do with a straight face.....