Diabetes increases the risk of vascular dementia. I fight this with the occasional puzzle. Ok, I admit it, I do the diabolical from sudokuoftheday.com every day. The puzzle from last Tuesday (12 January 2016) is rated diabolical with a difficulty of 17,500. The published solution uses the forcing chain technique on two occasions.
Can you spot the simple shortcut that solves this puzzle in a few minutes, without the use of forcing chains, guesswork, multiple path analysis, swordfish or any other convoluted technique?
Answer in a few weeks.
ps Howard from sudokuoftheday.com has confirmed the validity of my method.