As of today, my article with Carolyn Blume from TU Dortmund is available in the special issue of TESL-EJ on Global Englishes and translanguaging. It is open-access so it is available for free.
We used TED talks as online self-study, with one group watching talks by speakers of prestige varieties of English (so-called ‘native speakers’) and one group watching speakers outside of these prestige varieties.
The title says it all: there were no real differences between groups. Somewhat worryingly, neither group made gains in vowel learning, which was what we were intending they learned. Both were the same, although a limitation could be learners cramming at the last minute. However, this is something students do!