It seems like once people realize they're communicating with other real-life human beings, they are much more civil. Couldn't we try to consider that ahead of time, and avoid the off-handed negativity in the first place? It would make HN (and nonverbal communication in general) much more productive and enjoyable.
If the two comments combined fully capture your viewpoint, why not say something along the lines of, "Your advice is good and the post is fairly well-written, but it sort of comes off as a product advertisement. You cite scientific evidence, but you don't provide any sources, which makes it seem unsubstantiated."
Just a suggestion.
Or they're being honest the entire time, and simply posted about the negative part, because who wants to be that chucklehead going '+1' or 'Good post' ("that's what voting is for, dummy!")? Unfortunately, this then leads to comment sections coming off as negative and essentially being a bugtracker for a submission.
(Some relevant musings on this topic: http://lesswrong.com/lw/3h/why_our_kind_cant_cooperate/ & http://lesswrong.com/lw/372/defecting_by_accident_a_flaw_com... )
HN tends to err on the side of critical feedback, which is a reflection, in part, of the evidence-driven ethos that permeates hacker culture. This is generally a trait I hold in high regard, and take the downside as par for the course. However, I agree with the parent in that having some empathy for those we critique would improve the general tone of discussion here.
If the same content is rephrased in a "custom" way, chargebacks get cancelled, and you will start to get praise for having amazing customer support even if the resolution is the same and even if the final decision isn't what the customer actually wanted in the first place!
Health advice on internet should be scrutinized for the benefit of the readers (the "negative" comment, facts domain).
Content and its author are separate therefore the effort that was put into the post may be commented on separately for the benefit of the author (the "walking back" comment, social domain).
Though it is always great if a comment could be both honest and nice.
In the true spirit of HN let me 2nd what you are saying and wonder why the parent was so quick to back off what he said.
Although the OP has said he will provide links he also said this:
"I walked into the office on January 9th and suddenly had access to some of the most knowledgeable people on sleep out there."
So who are these people and what makes them so knowledgeable about sleep exactly?
I guess the real question is how do you say this "nicer":
'This post seems like one big, long unsubstantiated bunch of app spam for "zeo"'
maybe:
'I'd like some of the claims here substantiated. On the surface it appears to me that this well written post is simply app spam for "zeo"'
Maybe a reasonable litmus test for the HN crowd is: if the article was instead a speech at a conference, would you go up to the speaker afterwards (or during Q&A) and say what you're going to say? If not, why?