I'm pretty sure you can delete the following
<!-- write tree log to file -->
<logTree id="treeFileLog" logEvery="10000" nexusFormat="true" fileName="test.(time).trees.txt" sortTranslationTable="true">
<treeModel idref="treeModel"/>
<trait name="rate" tag="rate">
<discretizedBranchRates idref="branchRates"/>
</trait>
<posterior idref="posterior"/>
</logTree>
<logTree id="substTreeFileLog" logEvery="10000" nexusFormat="true" fileName="test.(subst).trees" branchLengths="substitutions">
<treeModel idref="treeModel"/>
<discretizedBranchRates idref="branchRates"/>
<trait name="rate" tag="rate">
<discretizedBranchRates idref="branchRates"/>
</trait>
</logTree>
But I don't think it will speed up...
Kai He