That's the way I've been taught by the guy who makes my eyeglasses too! I remember being slightly incredulous but took his word for it.

I only touch the lenses while soaping it, making sure that (liquid dish) soap is evenly distributed across the lenses. Then, I rinse them thoroughly in a stream of running water until I can no longer see water spots on their surfaces. I give the eyeglasses a slight tap to dislodge any excess water before wiping it with a dry clean cotton cloth I reserve for that purpose.