I'm currently using hodoku and use candidate colouring to highlight strong links. When I try and find loops, I use notepad/gedit, pick a cell, and then start seeing where I can get from there, and then try and make my way back to the starting cell. However I can rarely find a loop, and if I do, it doesn't eliminate any candidates. I've also tried using image editing software to draw lines across the sudoku grid, but this gets messy really quickly.
When finding AICs/nice loops, how do you do it? Just lots of trial and error? Any tips on how to find useful loops? I'm considering getting a pen and paper and doing the equivalent of a depth first search on every possible link, but this brute force method doesn't seem like it would be the best way to approach this.
Any advice would be greatly appreciated