Photoshop CS6 Postprocessing with color lab

Recently, discovered that color lab was better than RGB or CMYK for post-processing color photos.
There was a good tutorial on a blog that I found and I took it for a test drive.  See link below:

http://mauriziofecchio.blogspot.it/2012/05/my-workflow-for-hdr-my-tutorial-on.htm

You can watch an easy youtube video tutorial on how to use lab color at below link:

http://www.youtube.com/watch?v=UJdwZHzVkBY

Now for my own experimentation.
I had this dull looking landscape of Miami, which had colors which looked very tired as below. RAW/NEF image processed in LR4:

The below was the post-processed photo that I used with Colr Efex pro 4 with tonal contrast,
polarization filter and a graduated filter for bluing the sky. The photo is still dull.

Then, I used photoshop CS6 and did levels and curves in RGB and tweaked with hue and saturation, brightness & contrast and lastly sharpened the photo with unsharp mask with result as below:

I then processed it using color lab in photoshop CS6.

The color and luminosity now pops out and the photo was salvaged.