I've done it both ways. right under a 24 hour led under counter lighting and also in the darkness. both rocked the same progress.
when they crack they go directly into wet promix in a cup now. used to use jiffy, then rapid rooter, fuck both of them now. same with clones...FTW
rockwool cubes, rapid rooters, jiggy pellets.. same here.. I would use wool cubes religiously for more than 10years for any seeds and clones, then it was the rapid rooters since they're soo much more 'organic'... it's all bullshit, if you're growing in soil, start them directly in soil, if growing in hydro using wool, start them in wool. I don't do paper towel method anymore either. It is not necessary and can be a reason contributing to failure. So far this last while after having this epiphany, putting them directly in soil to germinate, I would say is 99.9% success rate. maybe 1 seed of a bunch here n there wont pop, but that's because of the seed quality/age not my methods.
I use a small round jar, and line it with whatever sandpaper i have around, this time I used a fine 100grit paper. Coarser 80 and below would probably be better. Place seeds inside and vigorously shake and spin jar around for a few minutes. Then place seeds in a small glass of regular bottled spring water for 2-3hours only, to suck up moisture into it's embryo, which by this time most seeds will be sinking or half sinking when poked and pushed down. Using promix with a small amount of worm castings added, with pointy part of seed pointing up, with 2 fingers holding the seed push down only about 1/2 an inch into the loose premoistened/not soaked/not soggy soil and lightly cover with loose soil and barely tap down on top. use mist bottle and spray the spot on top real good then place over in a corner of the veg room, or in 'the cloning station' under a flouro tube. if at any point the cups/pots are feeling light as a feather and/or the top looks just super dry, mist the spot on top with spray bottle real good and give your forearms a 1minute workout. 2days seeds are up. slowly bring them closer and closer each day to the main veg light and more direct wind from the oscilating fan.. within 4-5 days they are directly dead center under HID standing strong.