I recently think I got it myself. Actually, right now, I feel like I don't, again. So you're not alone, but we signed up around the same time. So we can be Soto-style Zen beginner buddies. Hahaha.
I think shikantaza, theoretically, requires faith or great understanding. For complicated minds like mine, understanding is crucial. I think for Rinzai folks, they think the same way... requiring various kenshos and a final satori before they settle in shikantaza. The readings about Once Born Twice Born Zen thing kind of struck me. Hakuin hated silent illumination because he couldn't get it, he couldn't settle the great matter. I honestly dunno how Soto settle the great matter. Not thinking about it seems like an escapism.
For example, this morning, my mom was telling me about a bus that fell over a skyway recently, killing at least 18 people. She asked me rhetorically why this had to happen to those innocent people and why so close to Christmas, perhaps expressing her disappointment, the dukkha of life. To me, living in the third world, dukkha feels so very very real. I feel as though it's not just something you can easily ignore like the boogey man. To do so would make me callous, apathetic. I can't seem to just not think of it because it's almost always right in front of me. So to sit in perfect contentment while faced with so much suffering is extremely difficult.
I mean, so many people came to Buddhism because they found that samsara was unbearable. You're born, you age, you get sick, you die. Even the intro in the Dogen movie moves me... seeing a little boy watching his own mother dying... telling him he must find a way to escape this dreadful existence. I sometimes get the feel that what's happening is that the great matter is being gently sweeped under the carpet, pretending it's not there. I probably misunderstand, everyone here seems like they have found relative peace. Moreover, Soto Zen appealed to the masses in Japan, usually the target of so much suffering. But to me, suffering seems so very real. And some things just totally unacceptable to accept.