Judging is subjective. Sometimes you get a bad draw. Part of the game. Two years ago, I had a robust porter score 44, 46, and 22 in three successive weeks. Guess which one of those weeks was the first round NHC?
On the BDSA example, the judge could have meant that although the individual components of the beer met ranges in the guidelines, that the overall beer didn't work as well. That's a hard point to capture, for many judges as well (particularly ones who judge so close to the guidelines that they don't try a wide range of examples). The "I prefer" bit could be trying to say how the balance should be tweaked, and to not interpret the individual changes as being something that would put it out of style.
Or they could not like Kasteel or Gulden Draak and couldn't wait to tell you.
The BJCP doesn't train judges per se. It has a system for evaluation, and a lot of training materials. Many people use them as part of training, but the results vary widely. There is no one way to judge, just like there is no one way to brew. Teaching one method as The Way is not something I want to see. The exam (should) measure how competent judges are based on how they practice their craft. That is what we care about.
If you don't like BJCP style judging, you should try going to a beer festival and seeing what is selected as people's choice. Or read one of those beer review type sites and see which beers are consistently ranked as best. Then imagine how your beer would be ranked using one of those methods. Reminds me of the Winston Churchill quote, "Democracy is the worst form of government, except all the others that have been tried." If you've got a better way to judge beer, let me know. Seriously.