1 - Interesting. Could have been a natural catchlight - even if the photog was wearing a white shirt.... Also could have been added in PP.
2 - Haha - wouldn't it be nice to have that answer. Many different scenarios - just read as much as you can. You're right though, the lower in the sky the sun is, the softer the light.
As for angles, this really depends, many different schools of thought and depends on the conditions. Generally - shoot people when it's cloudy if possible. If that's not possible, get them in the shade, but with sun nearby. If that's not possible, shoot them with the sun over their shoulders and fill with flash.
People will disagree, as there are different opinions, but this is lighting 101 with many people photogs.