I have expressed my opinion about SNS on the AHA forum and I was pooed-pooed. But the reason SNS works is very simple. You're pitching at high krausen. This is not a new concept, it's been around for a really long time. When yeast is at full krausen is extremely viable.
The key to a good pitch is the proper cell count, but more importantly, is the viability of the yeast. If the yeast is viable enough, the cell count can be reduced. English brewers would often skim yeast from the top of open fermenters and pitch directly into another beer. Lags times are reduce dramatically because the yeast are young and in a high metabolic state.
You can the same thing with a stir plate, just pitch when the yeast it's in high krausen. I often wondered why SNS was easier than a stir plate, I thought it would be the other way around since you don't have to touch the starter until you're ready to pitch. Just set it and forget it. You still have to build a starter either way.
I like to pitch lagers at lower temperatures, so build the yeast up with a starter, keep it on the plate for 12-14 hours and crash the starter at high krausen. It takes longer to drop the yeast, so I crash the starter several days before brewing. I decant the beer from the starter and pitch it @ 48F. Since I've been doing this my lag times on lagers went from 18-20 hours to 12-14 hours. I have seen as low as 10 hours with a standard pitch.
Pitching at a high krausen and high viability could explain why people get good results without much aeration. I don't recommend skipping the aeration of the wort, there is a lot science and research backing up the practice. I for one saw a massive improvement in my beer when I started aerating with pure oxygen and I'm not going back.
That's my 2 cents.