I had seen references to Hanover and RTJ Sr before, but never on their site (until I just checked and saw it). Frankly, I didn't believe it when I read it previously, but I suppose now that they have it on their site it lends a little more weight to the claim.
I've played a fair number of RTJ designs and usually see similarities in bunkering, green design, proximity of water to greens, etc. I've never played a RTJ Sr course that didn't, at moments, look like another RTJ Sr course I had played before. If Hanover was, in fact, designed by RTJ Sr. then count it as the lone exception; it looks nothing like any of his other designs I've seen. While this could be interpreted as a good thing, in this case, it is not.
Their site does only claim that the back nine is RTJ's, and the back is different and slightly better than the front, but it is hardly a standout. And I suppose that #12 does have some of his hallmark qualities about it now that I think about it. Nevertheless, Hanover is a very basic golf course and not a particularly good one at that. There is essentially one true dogleg on the entire course, and the front nine spends much of its time marching back and forth in parallel fashion.
The positives would be the low to the ground greens, especially on the front nine. They're very simple, yet provide a better challenge than you would expect at first glance. There is some decent use of the landforms on the back nine where the property actually moves a bit (the front nine is very flat), but it’s mostly greens perched on top of hills; hardly anything noteworthy but compared to the front nine it’s a welcomed change.
That area of the state is a bit of a wasteland for golf. I once worked about 20 minutes from there and it was a halfway point for me and a playing partner to sneak in a few holes after work so I played it maybe a half dozen times. It was purely utilitarian golf.
I’ve never played Morgan Hill, but have played Twisted Dune. This is a major trade down in quality and architectural interest from TD. Even Rancocas, another RTJ design not so far from Hanover, would be a step up and that’s not to say that Rancocas is a particularly good golf course either. I can’t speak for Tom Doak but using his scale and criteria it would be hard to say that Hanover is better than a “2” on its best day.
I will play golf anywhere, and have played more dogtracks than most. I’m not one to slight golf courses for sport. But if this is part of a visit to the area you could do much, much better than Hanover. I would suggest seeing if your partners would reconsider. If that doesn’t happen and you play there, I would echo astavrides; it’s less how bad it is and more how forgettable.