Interleaving Helps Students Distinguish Among Similar Concepts [pdf]
files.eric.ed.gov
files.eric.ed.gov
I thought this paragraph was interesting. Most interleaving research (that I’ve read) is within a single subject, and not across multiple subjects. The SRS/Anki proponents frequently recommend having a single “everything” deck, with interleaving being the main justification for that. This paragraph seems to indicate that having such widely different questions would be of limited benefit since the questions aren’t “difficult discriminations”.
I would love to see research that explicitly studies the idea of interleaving across different subjects.