Actually all that "SEO optimizations" are really work but they could be easily done for free by anyone who is able to use various online SEO checking tools like "SEO Text Browser" by
http://whois.domaintools.co and similars. The standard blog optimization package is easy as ABC - just install free SEO wordpress plugins (All-In-One-SEO, Google Maps, Tag Warrior etc), alter the necessary description, keywords when analyze it with SEO checkers. That's it!
In general, it really works and could bring you about 100SE hits a day even without internal PR links. But it wont make your blog really profitable however. To get really good SE traffic, you'll need to do something more:
1) Get as more as possible incoming PR links from other resources in a same niche.
2) Regularly update your blogs with quality and rich content, or use morphing tools to modify the syndicated feeds (one should never use unmodified feeds!)
The (1) and (2) are much more important that all the SE optimization tricks together. You may have a blog even without descriptions and/or keywords, but it will bring you 1000's of SE hits every day if your blog has a rich and unique content + regular updates.
Another way to increase your traffic are bookmarkers. You have to add some attractive features to make the ppl get back daily, e.g. daily/hourly rotating thumbnails, pics of the day, jokes, online games etc.