Well, I wouldn’t get too excited. At least the way a search through Server does it, there’s no way of restricting the search scope to particular groups, and you have to close all open databases except the ones you’re searching, while as always with DA the quality and quantity of summary varies unpredictably from hit to hit, and some databases report no results at all, for reasons I’ve never figured out. (It’s not to do with the DA permissions set for that database in DT’s app preferences.) And you only get one summary per document, as opposed to DT’s deep-drill view in the inspector of all the matches within the document with a few lines of context for each.
I agree that something like DA’s summarisation and digest features would be a fantastic enhancement to DT, but I suspect it would need to be implemented in-app rather than in DA, which is very specifically designed around web searches and whose interaction with DT depends on essentially fooling it into treating your open DT databases as a crawlable website. The value of DA searches of DT Server for me is less in the summaries (handy though those are in reminding me of what might be relevant in a file I wouldn’t have thought to look in) than in alerting me to documents already in my database that I’d completely forgotten about – quite often, embarrassingly, documents authored by me that already answer my own question…