> While SSSS provides information theoretic security, there are a couple of security gotchas. One example is that it leaks the length of a secret unless padding is used. In practice this isn’t usually an issue, since many applications (like this one) use SSSS for sharing fixed-size symmetric keys.

I also believe that also in theory, using SSSS + fixed-size symmetric keys gives you all the same security properties of SSSS and no leaking of the message length, assuming that the symmetric cipher you're using is secure. What exactly do you mean by "this isn't usually an issue" (emphasis is mine).