Tip: Selecting Luminosity Highlights and Blending

This tip comes from Swift Photography:

To add pop to your images you can use the highlights of your image as a separate layer that you blend with your image. You start by selecting the highlights -- either using command-option-tilde or command clicking on the composite channel in the channels (RGB channel). This creates a selection where the light areas are most selected and the dark areas are least selected. Then copy the selection into a new layer (command-j) and blend the layer into the original background using one of the light blending modes. As an effect, it works similar to how the clarity slider works in Adobe ACR or Lightroom but this gives you a bit more flexibility. You can then merge the layer onto a duplicate of your base layer and then blend that down to the base layer using another mode like luminosity to minimize the colour shift.

Here's an example using just the technique: