Interesting idea, although I am having a bit of trouble conceptualizing how you would prevent most of the water from going down the larger emergency drain during normal operation.
If you somehow designed some kind of a weir that directed the water only into the smaller interior drain, there may be some difficulty with tuning since you'd have trouble see how close the interior drain was to being "full". In a standard Herbie this is easy because you can observe the water level in the overflow space. It would be difficult to do the same in your design. You can't even observe which pipe (inside or outside) the water is exiting from in the sump since a truly silent herbie requires the drain pipes to be submerged in the sump.
|