Well, the issue is clearly underspecified, and different people read different things into it. I take your citation of the W3C blog entry that you are asking that caching should be employed. I read the issue entirely different, namely that by default no attempt to download the DTD should be made, or that the DOM loaders should provide better customization in that matter, or that catalogs shall be used.

Given that the issue was underspecified to begin with, I'm now closing it. Anybody who still has an issue here, please open a new issue and report your specific problem, preferably also proposing a solution.

If you need to follow up to this message, please do so in private email (martin@v.loewis.de).