How do you "ensure that the scalable feature of XSLT processor has been Enabled at the Template leve

We have a large number of people doing payment batches simultaneously. I have reviewed Tuning Output Post Processor (OPP) to Improve Performance (Doc ID 1399454.1) and tweaked the memory and the threads of the OPP. However, we still have sporadic complaints that it takes to long to process a payment batch and the time to create payments does spike from 1 to 2 minutes up to 10 minutes occasionally so I am reviewing the note again. On the note, in the section on the RTF optimization, it has this comment " Also, please ensure that the scalable feature of XSLT processor has been Enabled at the Template level." However, it does not provide any direction on how to do it.