Back in 2004, while bored in my college dorm, I learned the Ian Knot from this site. I've used it ever since. A few weeks ago, my 10 year old decided it was time to learn how to tie his shoes "dad's way". I was pleasantly surprised to see the site was still up, so I used it to help teach him how to do it.
I also learned it back in 2004 and it was one of the single most useful skills I have ever acquired. My shoes never come untied anymore. Coaching baseball, when a kid's shoe comes untied, I re-tie it for them with the Ian knot. Life changing skill.
If you noticed a change after you switched knots, you might have been inadvertently creating granny knots: