My personal oppinion is that it's always a better strategy to try to build a site which is genuinely valuable to its target audience and concentrate on creating high quality content and meeting the needs of your users.

While you may experience some short term benefit from this sort of short-cut method, it is exactly the sort of thing search engines don't want to work so you'll always be fighting against them and running the risk of being penalised.

You have an agenda: To rank well and drive volume. Search engines have an agenda: to provide searchers with what they probably want to find thus driving volume to advertising. If you can align these agenda by making yours a site that searchers will genuinely want to find, you will find it much easier to rank highly in a way that lasts.

It's better to try to improve your natural position rather than trying to artificially beat your natural position.