Some benchmarks have shown that this could lead to a potential performance benefit.
A possible explanation. In diamond-shaped CFGs (A followed by either B or C both followed by D), putting B and C both in between A and D leads to the code being less dense than it could be. Always either B or C have to be skipped increasing the chance of cache misses etc. Moving either B or C to after D might be beneficial on average.
In the long run, but we should probably do a better job of analyzing the basic block and branch probabilities to move the correct one of B or C to after D. But even if we don't use this in the long run, it is a good baseline for benchmarking.