The rule that the score of the offending team is reset to zero after an interchange infringement is archaic. I saw a reference to it is a Port Melbourne vs Preston game back in the early 1900s. The rule was introduced in an era where there was no interchange, no replacements, etc. As such, the only reason to be playing nineteen men was due to cheating.
Now we have interchanges. It's easy to get confused as Sydney did on Sunday, or as the Bulldogs did a year or two ago. But we also have an interchange steward, who probably noticed the infringement. We'd all be a lot better off if the interchange steward were given a whistle, and a single free kick were paid on the goal-line for an infringement. After all, we have a game where the on-field penalty for any infringement, be it a tap on the shoulder or a Barry Hall king-hit, is a single free kick (or a single 50m penalty, which is conceptually similar); making an error during a rotation should attract the same penalty, not a ludicrously out-of-proportion cancellation of the entire score - much like in hockey, where a "too many men on the ice" penalty is a two-minute minor penalty, just like everything else.
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