Google has only ever shown a sample of backlinks to a site - criteria for being in the sample has changed over time. It used to be >PR4 (or a very high 3) - a while ago that changed to somthing else; now it appears to have changed to a random sample.
The something else a while ago, might have been that pages called links.xxx were not shown in the sample and it did appear that this might have been the case for a while (its not the case now),
BUT:
1. If you looked hard enough in the backlinks to some sites (especially some high
PR sites), it was possible to find the occasional links.xxx page show up. There was definitly something that Google doing, so that most links.xxx pages were not showing up for most sites, however:
2. Just becasue a link is not shown in the backlink sample did not mean that it did or did not pass PR and was counted by Google, or not - thats were the myth started --> many jumped to the conclusion that just because a links.xxx page was not in the backlinks, it was not counted --- we now know that the myth was based on this false premise.
CBP