indyank - 11:09 am on May 19, 2011 (gmt 0)

I gained about 30% more traffic in Panda because I'm posting only unique on-topic LSI content, more than 1000 words on each post

You should remember that panda is run in several phases.Not all sites were evaluated in the first run on Feb 24.Google might be catching up with more sites in subsequent runs.

You might be wrong in your perception that your site fell within google's definition of "Quality". Rather, you might have gained the traffic because a few others were pandalized leaving some vacuum for your site to move up.