If you do what is suggested in the second link you give, that will work but is a manual process.
Not every page that someone authors should be included as an authored page - only the good, high quality articles so doing it manually is a way to ensure you only cherry pick the best content to claim authorship for.
If you use a plugin, you can end up linking back from everything whether you like it or not. Apart from only claiming authorship for your best content I think it is better to link back to your author page and then link once (per author) back to the Google profile. We created a WordPress plugin that does this called AuthorSure. It is used by a lot of multi-author blogs and gives you granularity of control over what you link to. If you happen to use WordPress and want a plugin solution it is the best one I know of ;-).
