Last year I made a suggestion at the nn Wikipedia about a second option of patrolling: namely a "no obvious problems" or "no obvious vandalism" option in addition to the current "mark as patrolled" option. Clicking this option would e.g. changes the colour of the exclamation mark to yellow, instead of making it go away altogether. This way, it is possible to see whether any other patroller has at all looked at the edit. When you now see a list of 100 unpatrolled edits, you cannot tell if a patroller has looked at an edit but is unsure if it should be marked as patrolled, or if no one has looked at the edit at all. This increases the risk of edits remaining unpatrolled and thus also for obvious vandalism remaining in articles. Presumably, it also makes patrolling in general less efficient.
The only feedback I received for my suggestion was positive, so it would be nice if we could have this second option implemented at least locally. It would probably also make sense to introduce a semi-autopatroller user class, whose edits are marked with the yellow rather than red exclamation marks by default.