When did 'jump the shark' threads jump the shark?

[Cannikin]

:shrug:

[Left Is Write]

1. When there were more than two.

[baldguy]

2. Oh the shark has pretty teeth, dear

And he shows them pearly white
Just a jack knife has MacHeath, dear
And he keeps it out of sight

When the shark bites with his teeth, dear
Scarlet billows start to spread
Fancy gloves though wears MacHeath, dear
So there's not a trace of red

On the sidewalk, Sunday morning
Lies a body oozing life
Someone's sneaking round the corner
Is the someone Mack the knife?

From a tug boat by the river
A cement bag's dropping down
The cement's just for the weight, dear
Bet you Mack is back in town

Louie Miller disappeared, dear
After drawing out his cash
And MacHeath spends like a sailor
Did our boy do something rash?

Sukey Tawdry, Jenny Diver
Polly Peachum, Lucy Brown
Oh the line forms on the right, dear
Now that Mack is back in town