Call me old fashioned in blogging, sitting working out bid-bots timing, working out whether or not they have ROI, IMHO looks and feels like gaming a system.
If you are gaming the system for more gain in marketing, then perhaps use them, off-setting expense against profits, each post would have to be calculated for profit/loss.
Back to old fashioned blogging, spend time and effort writing beneficial informative posts, people eventually start to enjoy and come back. Use tags and keywords, join great communities where people do enjoy content.
Thoroughly enjoyed reading the comments, it helps open ones eyes as to personal taste.
Yes, there is absolutely something to be said for old-fashioned manual curation and blogging techniques. I've lived by them for 13 years. :-)