Well, I am no priest of REST, but I think you are completely misinterpreting Mr. Fielding's point. That whole paragraph that you are quoting there is all about discoverability, at least that's how I interpret it. I mean, he even uses the word "bookmark", a concept which you seem to claim is incompatible with the approach. There is nothing in there that suggests you have to start at the one global canonical URI (which one would that even be? http://www.google.com/?), all it says is that whatever the initial URI is that you start at, the data you get back should be hyperlinked, using URIs, to any other resources that might be related to it, so that you can discover those related resources _without_ _prior_ _knowledge_ of _how_ _to_ _find_ _those_ _related_ _resources_, except through very general knowledge about the media type that the data is formatted as. Really, all that means is that a REST API that exposes a discussion thread and the postings in it, say, should not specify that for a given thread, the postings can be found as <thread-uri>/posting/<number> (because that would be out-of-band), but instead the document describing the thread should contain the URIs of the postings, so that general URI resolution mechanisms can be used to obtain them. In a way, it's all precisely about making things "bookmarkable", by using one common explicit addressing scheme for everything.
And that addresses can become dangling is completely besides the point. To solve that, you need a more stable addressing system instead of just not using addresses at all (which you really can't, if you think you can, you are confused and probably about to create an even less stable addressing system).