Nope, I had never seen that search page before. I've just tried it: depending on whereabouts I put the stones and exactly which diagram I enter, I get this page on maido (quite frequently), no results (quite frequently), hundreds of irrelevant results (if I make the pattern area too small), or the cathedral page you linked to (very rarely). The page about maido looks related, but doesn't link to the page about cathedrals or vice-versa. So it's actually pretty hard to find.

I suspect this is just a general problem: you don't want the search function to be too precise or too loose in its searches, but unless you know the exact diagrams in the page you want, you're not sure how precise or loose to be with your input. If my second diagram (the obvious starting point) was part of the cathedral page it would be a little easier to find, but there are plenty of sensible searches in which that page still wouldn't appear (e.g. diagrams with extra surrounding stones like in my second spoiler).