Welcome to Knitting Help!
That sounds interesting! I haven't heard or seen that type of cast on, but there are a lot of them. It's possible that it's something you "unvented" yourself! If it works then it makes no difference how you do it.
Here's one link that has multiple cast ons to check out. I've never seen so many in one place and have this one bookmarked. Get a cup of coffee or soda and relax..it may take awhile!