OK, @yeshe.tenley, Hi again,
I got some more time now, so I can answer in more detail. 
However, Yeshe, your question is just too broad to answer satisfyingly, I’m afraid. You want me (and others) to tell you what specific detrimental practical effects there can be for any individual who thinks something along the lines of “the Teacher [did] intend more than simply addressing the questions around survival/(non-survival) of beings after death”?…
For starters, I don’t even really know what you mean by “more than”.
Also, I agree the Buddha teaches “more than” this, even in the very same sutta. As Stephen pointed out, quite funnily imo, nothing is simple about this!
You’re summarizing my interpretation too narrowlly, I think. I say atthitā and natthitā are about the survival of beings, and so are the arising and cessation of the “world”, in a sense. But not the entire sutta, nor is that all there is to right view or even the entirety of Dependent Arising. So, judging by your summary, perhaps you have a too narrow notion of my understanding of these matters.
I don’t believe I make the exact separation between the two interpretations you seem to be suggesting. I don’t even disagree that insight into the mechanics of rebirth involves an insight in the non-substantiality of “dhammas”.
What do we both mean by “dhammas”, though? That’s perhaps the key point here. To me, it is life and experienced phenomena. For them to be non-substantial: that’s what it means for the factors of Dependent Arising to be without self. This what the Buddha explains in the Kaccānagotta Sutta too, albeit very succinctly.
I just disagree with interpretations which include in “dhammas” also the non-phenomenal, like insentient, unexperienced objects or even more abstract philosophical principles. By definition, such things can only be theorized about. Their nature can never be known through direct, empirical insight. And hence they are not a matter of concern of the right view of the Kaccānagotta Sutta. Well, they are a concern, in that they are specifically excluded from the “world” the Buddha wanted us to investigate the origin and cessation of.
But even then, I was challenging interpretations which tend to exclude rebirth in favor of other principles. I referred some examples in the footnotes of the essays you referred to. If, however, people acknowledge rebirth as a central principle in the Kaccānagotta Sutta, while they also add some tangential philosophical concepts which I think aren’t a matter of concern, then whatever! The difference is probably just a technicality, then.
That’s not what tends to be the case, though. Rebirth often becomes a side-issue, if not a complete non-issue, because alongside different interpretations of (n)atthitā the whole of Dependent Arising is often interpreted differently too. In that case, we’d be contemplating something very different from what the Buddha wanted us to. I won’t explain why I think that can be detrimental. That would take too much time, and it should largely speak for itself.
I forgot to say, but in all of that I was also challenging interpretations of the texts. I don’t intend to tell others how to practice. Anybody should practice however you want, of course. I’m just pointing out what I think the Buddha is telling us in the suttas. People can derive their own practical implications from that.
Here again, I don’t really know what you mean by “an expansive reading”, let alone for “one” in general. You’ll have to be more specific if you want a specific answer. And even then my answer will probably still be, “it depends”! 
Anyway, let’s say I include in the Kaccānagotta Sutta also the nature of, hmmm… geopolitics! I would still include rebirth as well, but also added geopolitics. The arising of the “world” in this case I take to refer to the arising of certain worldly affairs, the cessation of the “world” to their ending.
Is that going to help me, or will I “dilute the Teacher’s message” and therefore also diminish my practice? Will I waste time on contemplating matters which won’t get me out of suffering? Or would you argue that it’s helpful for me to contemplate geopolitics as part of my Dhamma practice?
I made up this extreme example because to me you made it seem like you think a more expansive reading just can’t be worse. I think you’ll agree that in my example that wouldn’t be the case, though. By expanding the scope of our contemplation beyond what’s encouraged by the Buddha, we will also be wasting some of our precious time on non-Dhamma. It takes away from what really matters to the path. So adding stuff can have negative practical consequences, depending.
An important thing to realize here, is that in the Kaccānagotta Sutta, the Buddha is limiting what right view is about. Although translated variously, he literally says “to that extent (ettāvatā) there is right view, Kaccāna”. He does this so that, once we understand how he defines it, we can understand whether we ourselves have right view, or more specifically, whether we do not. But if instead of limiting the scope of right view, we instead expand it, then we risk misjudging ourselves here.
The arising of the world to the Buddha is the arising of the self-less (or “insubstantial”, if you will) six senses through rebirth. Their cessation is the end of existence, the end the “world” at parinibbāna. If we haven’t seen these things as they really are, we don’t have right view. That’s what (I say) the Buddha is saying.
But someone else may think along the following lines: “Well, I don’t really see rebirth and its cessation, but I do understand the arising of the ‘world’ of momentary experiences (or the ‘world’ of insentient ‘dhammas’ or the ‘world’ of politics) so I have right view too.” I’m saying that in such cases, according to the Kaccānagotta Sutta, that person wouldn’t have right view. The stream winner’s insights actually revolve around rebirth. And to realize this, that can have very practical consequences for that person.
Those consequences I will again let speak for themselves, as it’s individual.
And I intend to keep it that way.
I think an internet board is not the right place to discuss practice too much.
I surely can!
I’ve written an entire book about it! (clickety-click here)
Thanks for explaining that, Venerable. It is, indeed.
… well, in context of this discussion on the “effects of practice”, that is!
Otherwise, my main concern is just to point out what the Buddha had in mind, and what not. My belief is that if this is done correctly—and I hope I personally do a decent enough job—then his words will naturally have the right effects on people’s practice, at least for those who are ready to hear these aspects of Dhamma I’m addressing.
So that’s what I’ll continue to do! even if people continue to point out (since dear yeshe is not alone in this) that in my writings I don’t tend to discuss the practical consequences much.
That’s on purpose. I think the suttas themselves, when properly understood, will point people towards proper practice.