[toni-a]

 I'm not saying right or wrong here but;

        My take would be not change the settings on the entire image if only the dress is blown out, but only to reduce the brightness on the dress only........ either by the highlight slider or the exposure slider using the adjustment brush in LR or PS. (RAW only)

  The adjustment brush allows "isolated adjustments" within an image to:

   Exposure. Contrast, Highlights, Shadows, Clarity, Noise reduction, Colour balance, Saturation, Sharpness etc.of course only in RAW.

  This way only the dress gets adjusted leaving the correct balance exposure for the rest of the shot!

Absolutely correct, however when you have 1000+ shots of a wedding to adjust things are not that rosy, having a good photo straight out of the camera is ways better, now you understand why the dress is a nightmare ?

Recently  

I stopped adjusting all the images, I let the couple chose the pictures they want to print and I do adjustments only on the pictures they want to print in large size (usually 30X45cm)