Whose guts? The notes in Henry Davenant's "Le livre des chansons," mentioned above, refer to the Scandinavian ballad "Elverskud" or "Sir Olaf struck down by an Elf" as the source of the tale.

Scandinavian version

In the Scandinavian ballad (verses 15 & 16 Babelfished) it takes a mere touch, or two, from the elf lady to strike down Sir Olaf. No guts involved on either side.