[quuxplusone]

I don't know that one, but here's a superficially similar joke from somewhere among http://miresperanto.com/humuro.htm :

When the British government invited commercial proposals for the digging of the Channel Tunnel between England and France, one man submitted a bid for only £10,000. “How can you possibly dig under the English Channel for only £10,000?” asked the project manager.

“It’s simple,” replied the low bidder. “My partner takes a spade, goes to France and starts digging. I take another spade and start digging from England. We’ll both keep digging until we meet in the middle.”

“Hm, I see. But what happens if, through a miscalculation, you two do not meet?”

“That’s even better for you!” replied the bidder enthusiastically. “In that case you will have two tunnels!”

[smoser]

An answer to your puzzle in another post that is locked: https://news.ycombinator.com/item?id=42498953 The "alternate" 5x5 word square that satisfies all the clues without using the words from the first grid is:

    S T R I P
    C H I N A
    R E G A L
    A T O N E
    P A R E R

Breakdown of the solution:

Across

STRIP (Remove the outer layer of, perhaps) — Counterpart to SCALD.

CHINA (Region on a globe) — Counterpart to POLAR.

REGAL (Like some movie theaters; e.g., Regal Cinemas) — Counterpart to ARTSY.

ATONE (Command to a lawbreaker) — Counterpart to CEASE.

PARER (Rhyme for Tom Lehrer /'lɛrər/) — Counterpart to ERROR.

Down

SCRAP (____yard; scrapyard is a common sci-fi setting) — Counterpart to SPACE.

THETA (It goes something like this: Ꮎ) — Counterpart to CORER.

RIGOR (Feature of liturgy, often; strictness/adherence to rubrics) — Counterpart to ALTAR.

INANE (It's vacuous, in a sense) — Counterpart to LASSO.

PALER (Fino is paler than Pedro Ximénez sherry) — Counterpart to DRYER.

[quuxplusone]

Yep, you got it! :)

[gabriel666smith]

A perfect joke, really.