A guide to local tipping customs has been found to contradict itself twice per page, prompting a traveller to resolve the ambiguity by leaving forty per cent.

The practice is considered eccentric locally and was received as such.

“Page nine says it is not expected,” said traveller Wilbur Anstruther-Doyle. “Page eleven says it is appreciated. Those are not the same. Those are not even close.”

The Institute for Gratuity Studies reports that no published guide has ever achieved internal consistency, because the underlying custom varies by establishment, region, hour, and the mood of everyone involved.

“There is no rule,” said Dr. Ludvig Marchetti. “There is a local instinct, developed over a lifetime, which the visitor is attempting to acquire during a four-day trip using a book written by someone who was also visiting.”

Institute research finds that uncertain travellers resolve the question by overpaying, then spend the remainder of the meal watching the recipient’s face for confirmation that they have committed an error.

Anstruther-Doyle reports that the waiter smiled, which he interpreted as gratitude, alarm, and pity, in sequence, over four minutes.

He has since adopted a personal policy of rounding up substantially and looking at the door.