NEWBIE QUESTION -------> "What make milled LFS so good for seedlings?" "Is standard peat too heavy, too dense for sowing?"
In addition to Steve's answer, standard peat can be used, after all you can buy those expanding peat plugs (just add hot water ) and cell packs as germination media. I'm not sure about the anti-fungal properties of peat vs LFS.
You can make your own milled LFS by crumbling LFS and/or scrubbing it through a wire screen.
Camomile tea misted on the seeds is supposed to be another natural anti-fungal.