I note that the Watt study was not pre-registered in the KPU registry. This may be because the study was done earlier than the start of the registry. There is a sleep lab dream study by Watt in the registry. It did not return significant results and was excluded from the meta-analysis, though.
Linda
I think feedback could be very useful, but it should be made clear that those who drop out after receiving feedback would be scored as failures in the final assessment.
Ideally, I guess, feedback would be given in a training phase, but then removed for the actual data collection.
My feeling is that many things in life require training - a child does not (usually) get on a bike and figure out how to ride it without assistance - at least of the passive variety - watching others. Training people to perform ψ is probably essential.
David