From that point of view, what are the point in infractions then?
In the past an infraction would have been my first instinct. There's never fully unstarred swearies anymore due to the filter so I reckon a warning should suffice. Usernotes are there to catch the repeat offenders, as like you say some don't learn.
:edit: Then again I guess maybe my point of view is "too soft" as I believe it was called in the past.
This was the point I was trying to make. It's efficiency at the cost of alienation. If the workload involved in giving infractions and potentially risking repeat offences is too much, then there aren't enough mods.