Yes, absolutely. I haven't heard the presentation by my colleague that you were privileged to hear, but the very fact that they framed the presentation as whether PR would lead to a higher grade, or is it a myth tells you that it has been an established system for not an insignificant amount of time. These works that Professor André Blais published before showed that PR did lead to holding everything as equal leads to greater turnout. Depending on what was cited, there are studies showing the differences. If there is interest in having literature, I would be happy to oblige.
I do want to say that you have to keep in mind that as a matter of method, depending on the study you're on, depending on what you control for, your results may be different.
I can't give you a more substantive answer, because I didn't see what they said, but it has been an established—