I think you're smart, Karen. I had low germination also, though I didn't stratify or winter-sow. I did find that pre-soaking helped a lot. Maybe the dilute peroxide was part of that help.
I don't direct-sow unless they spout and grow FAST, because we have very aggressive slugs (or maybe seedling-kidnapping Ninjas) that will mow seedlings they like right down to the ground as fast as they emerge.
I discovered the problem by scattering a little slug bait around the approaches to the porch where I hardened off seedlings. That made the slug trails visible.
My slugs LOVE Delphinium seedlings, but leave adult Delphinium plants alone.
