I was going to say it shouldn't add too much load, as the Armories already shows "recent guild members achievements" in the "News" section .... however, unless I've misunderstood what that should be, it doesn't seem to work properly ... I've just done exactly the same filter on our guild Armories site 5 times ... each time it provided a different result - several providing no results at all.
Our "recent achievements" widget seems to have stopped updating again. I try to do a manual update fairly regularly, in order to get the widget updated - I have just done a manual update now and the widget seems to be stuck on achievements gained on the 14th - I know for a fact that guild members have attained achievements since then. Is this likely to be a one off, or a more serious problem?