We just used organic miracle grow potting soil, covered, planted and went with it all in the same day. No sifting, no soaking and our tanks have done fine. So long as you do not move plants around like crazy for the first 6 months before the soil mucus builds up and sticks all the soil together you should be fine. Miracle grow has more mulch in it for the fertilizer part than regular top soil, top soil is more dirt. You could mix half miracle grow and half top soil if you wanted to. The soaking and drying repeatedly is to lessen the tannins that leach into the water and to prevent any beginning ammonia spikes, which if you do a fishless start shouldn't be a problem anyway. We never had an issue with ammonia anyway, i just read that part on the internet.
We didn't have a problem, our plants are growing splendidly and our fish are happy - with regular organic miracle grow soil.