Mother nature does all sorts of pretreatment: freezing and thawing, soaking and re-soaking, alternating temperatures, lengthening daylight. Some seeds only sprout after exposure to a forest fire. I think that's why wintersowing works so well. Mother Nature does all the work. All I have to do is plant the seeds in a milk jug and stick them outside in the snow. Mother Nature gives them every form of treatment, and I've never had damp off with any of the hundreds of jugs I've done.
I do try to be very careful for my indoor seeds. I still bleach my pots and trays, and cook the potting mix. I guess I've done that stuff for so long, I'm afraid not to now.
Karen