So can banned sites ever return I guess is the query?
I would suggest that you make sure you are on the up & up with all other sites you own (If any) before you do a re-inclusion request.
The minute you click submit on the request form... a Googler may just look at:
- All your sites sharing the same Analytics account ID
- All sites you may be running adsense on with the same pub-id
- All sites you have in GWT (Google Webmaster Tools)
- Don't forget Google is a Registrar also and may use that info to preserve the value of their index.
If they find others like the one they dropped, kiss them goodbye as well.
I had a drop-ship/affiliate site dropped from the google index in late 2007, after 18 months, many pages of very useful and well linked-to content, and 4 re-inclusion requests, I gave up trying. Along the way, I watched a few other very good sites suffer manual reviews and very obvious penalties, some penalties which still exist today.
Bottom line IMHO... if a site was manually removed/deindexed, walk away from it, clean up all others and be prepared for the worse, just in case.
Just my .02 cents.