"Not infrequently I walk a mile to the village pub and, while enjoying a glass of beer, do the quick crossword on the back page of the Daily Mail.
I usually manage to complete it, but a little while ago I was stuck on 24 across: 'Economical or frugal'
I wrote the letters and spaces in the margin at the bottom of the page T_R_F_Y, but nothing gelled.
As I walked home along a country road, I pictured these letters in my mind and recalled the clue. I do not like to be defeated and, after all, there were only 26 cubed possibilities, so I was confident I'd soon have the answer.
At that moment, a van passed me with a company name in large letters on the rear doors. The graphic style, together with the speed of the vehicle, made it awkward to read but, before it disappeared from sight I had it figured - and also the answer to 24 across: THRIFTY (as in Thrifty Car and Van Hire)"