I'm arriving really late to this, but Trout, this is probably the most significant paper I've read in years. It's pretty heavy reading, but the gist of it is that hydrogen peroxide does a hell of a lot more than just sterilize and kill off the nasties we face. It enhances signalling in the seed and creates a 'seed priming' situation that continues afterward in the seedling via 'priming memory'.
I am currently working with seeds from my early days of growing in the late '90s. I will be doing more research to come up with a seed priming technique that in part uses hydrogen peroxide. This paper really is a game changer as far as understanding the mechanisms involved.
Different seeds respond in different ways. I have already worked with a few things that have shown limited success: GA3 works but causes elongation. Finding the sweet spot (under 200ppm in my studies) can be a bit of a pain. After trying other methods this would be a last resort IMO. There are better ways to do it.
Fulvic acid and a single drop or two of Superthrive per gallon can be effective as a pre-soak. I also use an enzymatic sterilizer called Z7. How much fulvic acid can be difficult to translate with all of the different products out there; I'd recommend 10ml of Ful Power per gallon, but must admit that I've never done side-by-side comparisons to be sure that amount is best. (Note: humic acid will not penetrate cell walls the way fulvic acid does, so fulvic is preferred.)
Regarding the worm bin technique. This is well known in the agricultural industry as 'bio-priming'. The microbial activity does more than just defend your seed against nasties; it also signals the seed to activate its metabolism and resume cellular respiration, among many other things. The organisms found in worm bins are indeed also found in bagged earthworm castings, though at lower levels.
Earthworm castings are used in aerated compost teas, and with the right conditions the microherd in teas can easily meet or exceed what is found in worm beds. So those of you who don't want to hassle with worm bins should check out ACT as a great alternative to bins. Just pre-soak the seeds in your ACT.
Beyond that, I would think that truly rare seeds that are unlikely to ever germ should be tissue cultured. I will be diving down that rabbit hole this fall, hopefully, and setting up a small lab. Long-term preservation of strains and hybrids is something I really want to explore.