I don't really see how this would be useful
I don't know if you were talking to flabort, but I'm going to flesh out my ideas a little more.
Using a 2-bit system for such a large project does look daunting, but it makes you only need twice as many as the square root of the number of levers otherwise, where every lever is linked to one drop. So in a system with 16 things to drop, you would only need 8; in a system with 64 things, you only need 16. The larger the number of things to be triggered is, the smaller the fraction you need is.
Imagine a normal set of 16 walls to be dropped. with 16 levers. You want to employ a 2-bit system and only need 8 levers. Each wall has 2 supports or bridges holding it instead of one.
2 is a wall with 2 supports connected, 1 is a wall with only 1 support left, and 0 is a wall falling;
= is a bridge;
A and B are levers in different states. 1 is off, 2 is on, and on raises the bridges/cuts supports.
Group 1 determines which zone of 4 blocks will have 1 support released, and Group 2 determines which wall in each set will be released.
=2= =2= =2= =2= =2= =2= =2= =2= =2= =2= =2= =2= =2= =2= =2= =2=
Group 1 Group 2
A A A A A A A A
You want to drop the 2nd wall in the 3rd zone, the 10th wall from the left. You first select the third group by flipping the third switch in group 1, the zone determinant. This disengages one support for all walls in zone 3, walls 9-12
=2= =2= =2= =2= =2= =2= =2= =2= 1= 1= 1= 1= =2= =2= =2= =2=
Group 1 Group 2
A A B A A A A A
Then you select the 2nd wall in a zone, by flipping lever 2 in group 2. This disengages every 2nd wall in each zone, but only the one in zone 3 falls, because that zone is the only one with the first support also gone. That's how the zone is "selected". Now the 10th wall drops like you wanted it to, but with only 8 levers instead of 16.
=2= =2= =2= =2= =2= =2= =2= =2= 1= 0 1= 1= =2= =2= =2= =2=
Group 1 Group 2
A A B A A B A A
Although it seems more complicated, remember that it requires only twice the square root of the total number of levers it would otherwise. 8 levers in 16 isn't a big difference, but it's a huge difference to only need 480 levers instead of 57600 levers where you need to be able to trigger 57600 different events. You only need to set up things ahead of time, like using rows and columns. A 4x4 version of the example system would pick, say, row 3, column 2.
In summary, having a lever with multiple settings is equivalent to having a higher-base system, like having options 1, 2, 3, and 4 instead of just options 1 and 2. A higher bit system acts as multiple digits, options 11, 12, 21, and 22. A high-base system works well for smaller numbers of options, like when you want to be able to trigger one of 4 different things; a high-bit system works better when you want to be able to trigger one of 400 different things. Flabort's would be a useful addition to normal gameplay; my idea can already be done, but is limited to megaprojects.