I would suggest taking the time @Semaphore, as I have had a huge issue with robbing that is still ongoing which prevented me getting into my hive for over 11 weeks prior to installing the slats. If you search my other posts I have posted about this with pics of a screen I installed to help my hive defend itself.
Once I had the new screened bottom & slats built, I timed my entry for really early before the robbers arrived, and was dreading what I might find, as you can well imagine. To my surprise, my original 4 frames of bees had filled the other 5 with both brood & honey & if I hadn’t added another super might have looked at swarming.
What I found most interesting was that they had all their honey on the top inch or so of the frames, with brood & pollen below. Obviously, they did this to move the honey as far away from the entrance as possible, and this I believe will only be aided further by the slats.
Due to the robbing, I only made the entrance on my slat section 50mm wide, as a big front door is no longer needed with the bottom screen, In front of this I have a new robber screen [about 200mm high] that has a fully open slot along the front, but blocked with foam to about 20mm on one side. On the top section of the screen I drilled a 7mm hole near the front at each end, as i noticed that robbers get trapped & can’t escape, causing a lot of extra fighting behind the screen & this seems to be letting them out without them getting the goods. They are not climbing to take off - not dropping as they do either, just turning around for another go.
Meanwhile, my girls are coming and going at a steady rate, with no traffic jams like I saw on my first screen. So in answer to your thoughts, yes, most definitely, this setup is good for robbing prevention.