I finished my boosting yesterday, and the quoted information was current at that point.
In SM, I had the team on follow.
Would 'drop them off' and kill a bunch.
Then gather them up, move up a bit, and repeat that process.
I generally don't pull 50% of the instance in one go.
Rather go through an instance and kill as I go, groups of whatever.
My booster is a Frost DK, so can comfortably take out groups of 10ish in (depending on the level) 1-4 Howling Blasts.
My booster is not linked to the others.
So A>F and B>G, who are linked get parked at say Scholomance or Shadowfang Keep.
Aside from doing the quests once, they don't move.
And they get the RAF experience for the full run.
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