Yep. We have to add double filters to the events. Worth it only in those cases the of a mod that consumes too much processing...
Which may really just about anything -- not just mods like Autodrive that do lots of expensive operations on every tick. For example, my mod abuses on_built_entity to see if the keys are used to claim, lock/unlock, or summon a vehicle. This doesn't happen really that often (in single player mode, at least -- and relatively speaking, of course). But the event will fire for every single entity -- assembler, wall, transport belt, rocket silo etc. -- that is built, and as building stuff is a main part of Factorio, my function for that event will be entered very often. Same thing is true for on_entity_died: drive your tank through a forest killing trees left and right, aggro enough biters so they come running into your line of fire, or use nukes on a big patch of spawners, and you will see that function getting used very frequently. So event filtering could be very useful if it was implemented correctly.
Anyway, I've disabled it again for now. Makes little sense to use it because I still need the double filters -- and it prevents people who are using the stable version of Factorio from updating my mod. I'll add filtering again once the next version has been declared stable, which hopefully won't take longer than a few weeks. :-D
