TomD
So here is the challenge back at you:

1) I notice you use the term "cap iron". "Chip breaker" is even more common, or certainly common. What does that term mean to you, because to me it means the cap iron limits tear-out by breaking the chip. This may be true, but whether the explanation is true or not, it clearly indicates that the idea that the breaker might limit tear-out was known. In the Sawmill creek post below, they even discuss your beloved study back in 2009. Some say it breaks some don't this is a point in time, and they are just repeating what they have been told to believe in some cases. There is also a citation of the Bailey patent where the edge stiffening explanation is give, I mention for yucks.

http://www.sawmillcreek.org/showthread.php?111459-chip-breaker-questions-what-it-really-does

So if all this was unknown, why the term?

2) Second, just curious not probably a gotcha question. How did the study folks set up the study? What did they say was the reason for the info, where did they get the idea breakers worked as their study showed? Are they under the impression this stuff is new, or did they read it in FWW?

3) You can easily find video or pics of Japanese hand planes being used in a way were the shavings waft straight up without curl. Where superb finishes are created. This happen according to the beloved study, when the breaker is adjusted very closely to the edge. The planes are designed to allow that. So how did that happen if nobody knew about it? In terms of how you think about this stuff, how can these facts that planes are doing this stuff all the time, square with the idea that the nobody knew to do it. It is theoretically possible, but not in the real world.

(even our power tool jointers and planers have chip breakers on them. And you can find threads where people discuss them and tear out. Which again, may or not be good thinking, but shows the widespread association)