Unfortunately, I've found articles on this site to be poorly articulated opinion pieces, written from broken premises and with incorrect information, rather than actual UX practice documentation. Comments that disagree and point out errors are routinely deleted; a response to the one comment of mine that has remained live included the line, "this is a blog, not a science lab." One of the differentiators of UX from art is that it can be tested, so I find the author's attitude professionally disappointing.
LukeW's seminal book, "Web Form Design" has an entire chapter (19 pages!) about label placement. Some notes:
About 30 seconds into reading the article, I came to roughly the same conclusions as you. No references to primary research. Poor.
The sad thing is that many people accept what they read in blog posts that are widely retweeted. Critical thinking is such an important skill, I'm surprised how many people don't have it. ( http://en.wikipedia.org/wiki/Critical_thinking )
What you are asking for is for the research to tell you how to think and to validate the idea for you. That's somebody else's work, not yours. So you are wanting them to think for you, instead of thinking about the idea on your own. That's not critical thinking.
Critical thinking involves using your own mind to think about an idea without research. Not many people can do this.
Ideas are presented all the time. You either agree or disagree. If you are curious for evidence, then you do the research yourself. But don't agree or disagree on the basis that no research is presented, or on the basis that lots of research is presented. Either way is not critical thinking.
Comments that detract value or are off-topic are deleted. You can still disagree and add value, but unfortunately your motive so far has only been to detract value, which is professionally disappointing.
LukeW's seminal book, "Web Form Design" has an entire chapter (19 pages!) about label placement. Some notes:
This paper is cited as discussing a major eBay form design, explaining their methodology: http://scholar.google.com/scholar?cluster=106605571117736457...
This article is cited as having done the eye-tracking research for label placement: http://www.uxmatters.com/mt/archives/2006/07/label-placement...
The chapter starts out with the note that "it depends" for your specific usage.
A summary of the results are available on his blog: http://www.lukew.com/ff/entry.asp?504
He also discusses using inline labels on his blog: http://www.lukew.com/ff/entry.asp?687