[EM] IRV (not PR) fosters peaceful democracy?

[Warren Smith]

My "asset voting" scheme is an unconventional PR system, which may foster more
peace and less extremism, than other PR systems such as party-list.
Since it has never been tried, it is hard to tell...
  http://math.temple.edu/~wds/homepage/works.html
#77 dscribes asset voting
#91 is a survey of multiwinner election methods

Is there some reason to argue that IRV leads to more peace and/or less extremism
than other single-winner systems?  It seems to me that IRV leads to 2-party domination
just like under plurality, which I suppose you can call non-extreme since
the other parties get nothing, but I don't like it much.
wds