I suppose that one way to test #2 and #3 is to ask the participants (informally, so it does not appear like a test) how useful or successful they think some other skill learning activity was. This is probably a part of the procedure already. There is a significant pressure to say that “they learned a lot and are now better at it”, due to several biases, including motivated cognition. When asked to elaborate, they are likely to put forth a number of arguments. To a trained eye, it should be easy to spot whether a particular argument is in fact a rationalization. For example, any immediate supporting argument that is not a specific example of successfully using the relevant skill is very suspect. Some of the better replies would be along the lines of “Wait, how do I know whether this activity was helpful?” and “OMG, I caught myself wanting to rationalize that it was! I guess I did learn something, after all!”
I suppose that one way to test #2 and #3 is to ask the participants (informally, so it does not appear like a test) how useful or successful they think some other skill learning activity was. This is probably a part of the procedure already. There is a significant pressure to say that “they learned a lot and are now better at it”, due to several biases, including motivated cognition. When asked to elaborate, they are likely to put forth a number of arguments. To a trained eye, it should be easy to spot whether a particular argument is in fact a rationalization. For example, any immediate supporting argument that is not a specific example of successfully using the relevant skill is very suspect. Some of the better replies would be along the lines of “Wait, how do I know whether this activity was helpful?” and “OMG, I caught myself wanting to rationalize that it was! I guess I did learn something, after all!”