I can see both sides of the argument, but I land on the side of "it's great." Sometimes I do question it because it doesn't have any particular thing that blows you away, but I never convince myself otherwise.
I think the greatness has a lot of it has to do with pace and scale. That makes it add up to way more than the sum of its parts. I played it twice on consecutive days (one of those the afternoon after a morning at Castle Stuart), and would have readily gone for a 3rd if time allowed.
I loved TOC as well, so if we leave that out and compare against other top courses on the trip (and I realize I'm being really critical about really great courses):
-I did a 36 day at Cruden Bay, and while I absolutely loved it....that's a really tough day even without any poor weather. I was not ready for more golf at the end of that. As an exploration of the land, it's cool how it uses the dunes to the north and the dunes to the south, but there's something that feels strange about the layout on the property. I can't think of another great course that cocoons the lesser course, which is the one you're looking at from the clubhouse. The flatter points of the round do come at perfect times as respite from the uphill climbs.
-I enjoyed the inward 9 at Aberdeen more than most, but it's the pacing of the holes that was more problematic for me than the actual content. If courses were like albums where you could custom shuffle the order of the tracks and mix the inward and outward holes in a different order, that course would feel a lot different. No artist would put all the bangers first and finish with all the ballads.
-North Berwick would be the closest comp for pace and scale with quality, but the difference in quality between the outward and inward 9's is so stark. There also isn't nearly as much interesting elevation change.
-I really liked Castle Stuart and Kingsbarns start to finish, but they both lean toward the "too big in scale" side and don't beat Dornoch in terms of hole quality. I had a few other quibbles with Kingsbarns, but that's not the point here. I personally always deduct points for returning 9's as well because it feels like every other formulaic course built in the US, particularly if it's 2 5's and 2 3's on each 9 for par 72. That formula feels like a straight IV of aspartame.
-The closest comp to Dornoch from my trip would be Elie, but hole by hole Elie doesn't come close to stacking up. I can't speak for the real ringers out there, but I'd imagine Elie at 6200 yards from the tips couldn't hold their interest nearly as well. Elie also has only 1 hole over 450 yards, so it's not testing the whole bag of shots nearly as much. On the other hand, Dornoch is just fine for a weaker player as well. A lot of Dornoch's meaty holes are bunched up between 7-14, but it gets teed up by a short 4 and a 3 and then has 2 3's sprinkled in between.
Finding comps elsewhere, I'd compare to #2, Bandon Trails, and Jasper Park. All are intriguing 1-18 yet don't have to resort to crazy scale (other than Jasper's mountain scenery that isn't in play) for intrigue. If the complaint about #2 is a lack of green variety (I'd kill for a funnel pin SOMEWHERE in the round..can we import the 8th at Pacific Dunes or 18th at Old Mac?), Dornoch has some green features that can be used to help you rather than repel the ball. The left sides of 3-8 at Dornoch are helping slopes with 8 being a downright funnel. 10 has 2 ridges to help you stop the ball if it's down wind. 13 and 18 also funnel toward the center. Maybe the greens themselves are elevated, but all those other slopes result in approach and recovery variety.
For being an out-and-back routing, the slight S shape plus the reverse direction on 17 prevents playing too many consecutive holes into the same wind.
Depending on how I scale my Doak scale, it feels like 9 has to be the floor if I'd take Dornoch head to head against all of those courses. Let's ask the reverse question...what would improve Dornoch, no matter how much of a fantasy land idea it is (like mixing the order at Aberdeen)? What would make it better? What is it missing? It has variety, scale, pace, setting, 1 of the best holes in the world, plus every single hole is at least "very good". That all adds up to a great course to me.
(came back and edited here because the font sizes got jacked up)