I've found evil sudokus at www.websudoku.com very difficult. I can't solve them without pencil marking. Well, I solved one with websudoku's own pencil marking and it took over 50 minutes for me. Websudoku said average time for evil ones is something about 20 minutes and I was confused. Are players really able to solve them without pencil marking or what? After that I tried Simple Sudoku software and found how easily evil puzzles can be solved with it, because Simple Sudoku does pencil marking automatically. Then I started a new evil puzzle at websudoku and wrote initial situation into Simple Sudoku, solved puzzle with it and then wrote result into Websudoku. I managed to do that in six minutes.
I ask, is that 20 minutes average at Websudoku done with helpers like Simple Sudoku, or are other players just so fast?