Here is the HTML version of the scholarly article mentioned in Time (they stated both HTML and PDF were free, so hopefully you can access them):
I too thought that I didn't use any study techniques (just paid attention). But when I looked at the actual scholarly article I found I did a couple of things not mentioned in the OP, but was mentioned in the APS article (and in passing in the Time article).
Namely, I did the following instinctively (though I did not know these were "study techniques"):
1. Elaborative interrogation Generating an explanation for why an explicitly stated fact or concept is true
2. Self-explanation Explaining how new information is related to known information, or explaining steps taken
during problem solving
What minimal "Studying" I did do, fell into the following:
8. Practice testing Self-testing or taking practice tests over to-be-learned material
9. Distributed practice Implementing a schedule of practice that spreads out study activities over time
10. Interleaved practice Implementing a schedule of practice that mixes different kinds of problems, or a schedule of
study that mixes different kinds of material, within a single study session
The numbering used is the order that they listed in scholarly article, not my own preference.
But I only used any of the above three techniques out of desperation (IOW, when feeling like I wasn't actually learning anything but still wanted to pass some tests).
Considering the article mainly reviewed studies that judged the effectiveness of techniques with tests, I don't think it should come as much of a surprise that the practice-test based preparation was better preparation for the tests themselves.
If we judged effectiveness of learning by probing the students 10 years later, I think we would see very different results.
A few of the "study techniques" that I am very disappointed to not see are:
1) Making use of what I learned to process the world around me on a continuous basis.
2) Thinking of projects I can create or products I can invent based on what I have learned.
3) Discussing and debating things with colleagues, friends, strangers, or whoever is willing based on what I've learned.
These are pretty high on my list for what I naturally do when I "study".