Concerns of Define-XML stylesheet and performance

[lexjansen]

From Trevor Mankus:

I'm reaching out with a question about the stylesheet that you authored which is bundled in the CDISC Define-XML package.
One feature we have in P21 Enterprise is the ability to preview a define.xml so you can see the output in a modern-day browser. We've recently had a few customers of ours reach out and ask about how long it takes that page to load. We've had our engineers look into this and are starting to think it may be related to the stylesheet itself that is parsing the XML content.

Our engineering team reported back with "the define stylesheet uses a double loop on Value Level records".

I'm attaching a sample define.xml that reproduces slow load times. It loads locally in about 8 seconds. Have you seen anything like this before or heard of any other issues? Any idea if there are ways the stylesheet performance can be improved?
CDISCPILOT01.xml.txt