XSLT solved this problem. But it had poor tool support (DreamWeaver etc) and a bunch of anti-XML sentiment I assume as blowback from capital-E Enterprise stacks

XSLT solved this problem. But it had poor tool support (DreamWeaver etc) and a bunch of anti-XML sentiment I assume as blowback from capital-E Enterprise stacks going insane with XML for everything. XSLT did exactly what HTML includes could do and more. The user agent could cache stylesheets or if it wanted override a linked stylesheet (like with CSS) and transform the raw data any way it wanted.