Message Filtering and the effect on Batch View.
If you have someone filtered out and some of their messages are in a batch of, for example, 10 messages you're viewing in Batch mode, the number of messages you'll see won't be 10. It'll be 10 minus the number of posts they wrote.
This is not likely to change. The technical explanation is that I use a stored procedure to grab the 10 posts (much more efficient that way), and it'd be a ton of overhead on the database server to parse your filter "Criteria" field to exclude the user numbers in it then deliver the 10 remaining results. Easier for me and for the system to just deliver the 10 messages, then let the webserver determine which ones to show.
If your Filter Criteria for Public Messages has so many user ID's in it that you find yourself getting too few messages, you can bump up the batch size to as much as 100. And in the big picture, viewing 100 at a time is easier on the system than viewing 10 at a time 10 times. One hit versus 10, and it being a 10-times-larger hit doesn't increase the workload for that hit by anywhere near a factor of 10.
Oh, and don't read too much into the fact that this aspect of Filtering was the first to be implemented. It was done that way simply because this was the easiest part to implement.
