Certainly share your concerns and opinion, agree that the MDR is a major part of an enjoyable experience on a typical cruise. I wouldn't necessarily shun the Coral Princess as I doubt the MDR problem is ship specific. It is worth while to note there were others who were on that cruise with us that have posted good things about the MDR. Perhaps we are getting a little curmudgeonly in our old age and expect too much. We are working toward 600 days voyaging.
As I alluded to, I believe all 11 of the majors are downgrading their product in certain areas. Meaning, less staff and poorer quality cuisine in their main dining rooms all the way around. For instance, 11 months ago we were on HAL for over a month, starting out it looked like the MDR was going to be not so hot, but they got things under control after the first day or two out, then in September we were on Princess for 19 days and again things started out poorly in the MDR but smoothed out slightly there after. I believe Princess has now cut back so far they can't get the limited staff to adjust anymore, that I also believe is what is going to happen to all of them.
My guess is the folks who found the MDR okay on our cruise were in "Traditional", which probably would be the way to go if one can tolerate "Traditional".
For us, long ago we got away from traditional when the cruise lines started offering open seating. Reasons we don't like traditional are: 1. You are locked into eating at designated times only. The late is way too late for us anymore and the early often coincides with the ship's sail away on port days. One of my favorite likes when sailing is the sail away, so I don't want to be down in the dining room feeding my face when I could be on deck taking every thing in. Also, there are many other events and things happening that conflict with traditional dining times at times, for us anyway, so it is awkward to have to keep letting the restaurant staff know you won't be there for dinner. 2. Some of our voyages have been months in length, it used to be hard to get a table for two in traditional seating, therefore you had to go with the luck of the draw in that you were seated with sometimes two or three other couples. If you didn't like them, tough, you were stuck with them for the length of the voyage. Now, we were fortunate and never ran into someone we really didn't care for, except once or twice, but witnessed a lot of horror situations.
In summary, for us, it looks to me like a pay extra for dining in the specialty restaurants or use the buffet area when you don't want to shell out unless the MDR works out for that cruise, is the future. Sometimes the buffet areas can be quite good, unfortunately, if they are busy, some of them are terribly noisy.