Correcting Highlights? Watch Out For Open Shadows!
If you open the Shadow/Highlight command (found in the Image menu, under Adjustments) to open up the shadows in your photo, you're in good shape from the get-go because it automatically increases the shadow area by 50%. That's great, if that's what you're after. But what if you're trying to pull back the highlights in a photo? Shadow/Highlight doesn't know that and by default still opens up your shadows by 50%. The way to combat this is to immediately drag the Shadows slider all the way to the left when the dialog appears, so now you can adjust (pull back) the highlights by dragging the Highlights slider to the right, which now affects just the highlights and not the shadows.