Welcome to Michael's blog. Michael Andrew, (aka Michael The Maven) is a freelance producer, photography instructor, tech innovator, and when needed, disaster aid specialist. Disclaimer: Michael is a participant in Bhphoto & Amazon affiliate programs that provides an advertising commission if you purchase through links on this website.
Just like the Joe Edelman says in his video; its summer and people can look hot and shiny in your photos. Not to say they don't at other times of the year it just seems to be a much bigger problem in the heat. You'll probably run into this problem often if you're shooting wedding or doing senior portraits.
This minor issue is easily corrected in both Photoshop as well as Lightroom. Joe also points out, and this is something I've already said, it's always best to get things right in-camera but if you do find yourself in this situation with an otherwise great image, no need to get rid of it.