In the latest google webmaster hangout with John Mueller of google, John debunked the myth regarding crawl rate penalties.
The question was surrounding the myth of if a site has "some" penalty then google bot will come around less.
You see this myth popping up all the time with people "seo's" asking "has your crawl dropped" then applying the drop to a penalty.
In my opinion crawl rate is 100% worth monitoring but in regards to deep crawls, updates, structure problems.
Barry over at search engine round table has a post about it with the video here: http://www.seroundtable.com/google-crawl-speed-penalty-18720.html