Sudoku – From the Japanese meaning, “Not as hard as a crossword”

Last Friday I was riding to work on a packed tram. Normally I get on early enough into the route to secure a seat but because there had been a hold up there was a flood of commuters waiting and when the #96 finally turned up I had to stand. I was hanging swinging from a hand loop like a planter hanging basket full of fuchsias, when, just as we passed the casino, I glanced down at the lady seated to my right. She was busy at work on a Sudoku puzzle (difficulty: tedium) and after sucking on the biro for a moment she filled a ‘4’ into a box just off centre of the puzzle. It was too cramped to read in any comfort so was easily hooked by this woman’s scratches.

I studied the grid a little closer and realised that she shouldn’t have placed the “4” there. There was already a “4” in the bottom of the column and based on the answers she’d filled in so far, she should have in fact placed either a “1” or a “3” in the box. I had a huge compulsion to point out her mistake but then that opens a whole jockstrap full of crabs as it would reveal that I’d been spying at her puzzle over her shoulder.

What is the etiquette in situations like this? Should I point out the failings of a stranger or leave the status quo knowing full well that placing the “4” in the wrong place has thrown every other placement out of whack in a move similar to a butterfly beating it’s wings in China. At this point her mobile rang with a horrible polyphonic explosion of Kung Fu Fighting. I relaxed and let my staid, non-confrontational side win. If she thinks its amusing to inflict faux-Asian 70’s pop on the rest of us then fruitless repetition followed seething rage as she realises her mistake is far, far less than she deserves.