We present formal techniques for improving the performance of group communication systems built with the Ensemble toolkit. For common sequences of operations we identify a fast-track through a stack of communication protocols and reconfigure the system's code accordingly. Our techniques are implemented as fully automated tactics of the NuPRL proof development system and are based on an embedding the implementation language of Ensemble into the logical language of NuPRL. Together with verification techniques to be developed in the near future they will lead to a logical programming environment for the construction of reliable and efficient group communication systems.