This one might be a bit obscure. I don't remember seeing a lot of other people using Pursuit of Knowledge. Even Scalpelexis had its fans, and while Bubbling Muck might not be highly renowned as Magic cards go, it was played extensively in tournaments once upon a time. But Pursuit of Knowledge, to the best of my knowledge, never really caught on. If I had knowledge of it having made an impact somewhere, I'd acknowledge that. Anyway... In my hazy recollection, while I used the card myself, I never actually played against it. So I've seemingly been the sole advocate for Pursuit of Knowledge. Obviously, this is not true. The card features gorgeous Tony DiTerlizzi art, so somewhere out there are people who like it for that alone. And the Gatherer comments do show some distinct appreciation for the card, with a solid average rating (4 out of 5 stars) too. It's a niche rare from Stronghold that was never, ever reprinted, and is isn't so good at any one thing that it does for it to really capture the attention of the EDH crowd or anything. So my guess is that those of us who were playing casual Magic back then and thought it would be a useful inclusion in our decks have fond memories of Pursuit of Knowledge. To anyone else, it's just some old bulk rare.