I've used this method to tie all my shoes for more than a decade and it holds much better than the granny knot, which I'd guess is probably 50% of people (as whether not you end up with a granny or a bow knot is just the toss of a coin). The benefit of Ian's tying method is that it is impossible to end up with a granny knot.
My shoes never* come untied, without needing to resort to a "double-knot".
* Except my Sperry Docksiders, which have leather laces and don't seem to keep any kind of knot very well.
Maybe I did the Ian knot wrong. Don't have a problem with the knot I use so not investigating further.