XSLT rendering is slow, I started to think about whether it would be possible to store pre-rendered HTML in zebra or elastic, so that we only have to run the marcxml to html xslt transformations at indexing time rather than per, search. It's a time vs. space optimization, and I don't know if the html generated by xslt ever gets cached; if it does, we might not see any benefit. Anyway, putting it out for discussion.