I think it's more that the refs back then could be bothered adjudicating the straight feed, Lee.
Back then, the ref set mark, the players formed a scrum, and then he watched the feed.
In the 90s, referee controlled scrums were almost depowered and since that time hookers haven't really hooked.
I played a few years with an old guy who was ex-Parramatta reserve grade, and he could hook like a prize fishermen - really flexible through the hips. One time he got his knee up so high for a strike that he got me on the forehead!
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I hate autocorrect ...