[At the end, the whole town helps the Simpsons to rebuild their home. Homer tries to hammer in a nail while shingling the roof, in the same manner as earlier]

Steady... Steady... Steady...

[Bart remembers what happened last time, and gives Homer some safety goggles]

Here you go, dad.

[smiles]

Thanks, son. [concentrates on the nail again] Steady... [appears to hammer it in successfully] Woohoo!

[As he stands up in triumph, he realises he has actually hammered it into his leg]

WWWWWWWWHOOOOOOAAAAAAAAAAAAAAAAAAAAAAAAAAAAHHHHHHH!!!!!!!!!!!!
[He runs across the roof in agony, dragging the linked shingles along with him, until he stumbles off the roof. Bart laughs at him.]