Not every Yak 52 pilot flys run & breaks (I don't because there is no need) however, some would argue that there is a need when in formation. That, of course, is up to them - the BIG proviso being that this type of circuit join is not a civilian procedure.
Pilots flying R & B joins should realise that they may be doing something that is totally unfamiliar with others. Furthermore, on busy day it may simply not be possible to fly such a join.
Not all Yak 52 pilots are ton-up hooligans - lots of other pilots make all sorts of strange attempts at circuit joins and patterns.
Fly safe