Author: H.User1325 (25 Aug 16 9:26am)
There is a difference between a "hidden" link similar to:
<img alt="" src="https://www.tracking_link.com/pixel.gif" width="1" height="1">
and "links" that are hidden so that only scrappers see them, such as:
<!-- <a href="http://www.link_to_hp.com/gateveiled.php">cashandcarry-abdomen</a> -->
Note that the actually causes a request to the remote server and the second may look like a link but is really just text within a comment.
Not to sound like a nit-picker, but there is a difference between a "hidden link" like my first example and an "anchor" ( <a href="xxx"> see this </a> ) Even when the visible part of the anchor ( see this ) is hidden from the screen of the browser by placing off screen, not having a visible part etc.
Anecdotally I manage four domains that with hidden honeypot links on most pages and they are all will indexed by Google and other SE.