After reading the Post by ZOOMPF http://moz.com/blog/improving-search-rank-by-optimizing-your-time-to-first-byte I was wondering if any of you have optimized your TTFB and noticed improvements in rankings.  Have you optimized and not noticed any differences?

I know people have mixed feelings towards submitting their sites to directories, but this one really seemed special, so I decided to share the opportunity with the Moz community, as well as open up a discussion on the value of being a part of this directory (and similar ones.) We recently submitted our site to Dial a Human (www.dialahuman.com) It is a directory of companies' phone numbers, which go directly to a person (bypassing the machines.) I think this directory actually does provide users with value, and is far from your typical link farm. The Page Authority is 56 and the Domain Authority is 47, and it is a PR5 site. The other companies listed are all extremely reputable (most of them are fortune 500 companies.) The fee to join is $75-$150, but to be included with this group of companies, we felt it was very worthwhile. We would join this type of directory over and over again.  Would you? If you have any other directories which are of the same caliber please share!