Putting multiple leaves inside the switch makes the switch EXTREMELY tactile. I really mean it, it's extreme! They're pretty much unusably tactile, but it's funny to try it out. I can pretty much guarantee that Alps with multiple leaves is the most tactile switch out there.
In order to fit it in the same space, the top tabs must be bent out (if you're using a tactile leaf) and only one of the leaf's bottom tabs on the side can stay unbent -- the rest has to be bent. You can also bend the long bottom tab if you please, but I didn't do this.
I used some random leaves that I had lying around to do this experiment. In this case, it came from an unknown Alps clone that uses a compatible leaf to the SKCM/SKBM series. I would guess that this came from the Shigi switch. It uses a clicky design, with the recessed tabs and all, but the leaf doesn't actually click inside the Dampened Cream switch, which is pretty strange. I also stuffed the original Dampened Cream Alps leaf into the list.
Two leaves seems to fit fine. I had to just press the leaves inside the top housing if I was going to use 3. I haven't tried using more than 3 leaves, but I doubt that more than 3 leaves can even fit.
Using 2 leaves seems okay; the spring in the Dampened Cream switch seems to still be able to push the stem back up.
Using 3 leaves and the switch struggles to push itself back up, though when I put on a keycap it seems to work fine for some reason.
Again, I haven't tried using more than 3.
The scratchiness also became apparent in the switch with multiple leaves. With 2 you don't notice it that badly, but when you use 3 leaves, it becomes a big deal.
Using 2 leaves might be a nice choice to prevent accidentally pressing a switch; it has enough tactility that you need to confirm yourself to actually press the switch.
Using 3 leaves is just comical.
I would really like someone else to try this experiment and get the force curves out of at least one of the results. It would be hilarious to see the graph! "Uwaaaa! A 100g tactile drop!"
Try it yourself!
