Users sometimes imagine that just by running an application under Saxon-SA instead of Saxon-B, they will automatically get a performance boost. Sadly, this isn't the case. Sometimes Saxon-SA's more powerful optimizer will give a dramatic benefit, sometimes it will give none at all. In fact, sometimes if you move a workload to Saxon-SA without change, you see a performance regression. This is caused by the fact that Saxon-B can assume all nodes are untyped, whereas Saxon-SA can't make this assumption....   more »