Now I understand why you didn't think that the Curse of Monkey Island soundtrack wasn't notable!
It works the other way around too, actually. When the Monty Python team showed the Holy Grail, they noted that people didn't laugh at their jokes while music was playing in the background. So they made sure that there was no music playing whenever a funny or an important line was said. (Except for the shruberry line, that is.)
I sometimes actually do manage to enjoy soundtracks while they are played along with text, a notable example being
Hardtack and Trenchfoot's theme from Tales of Monkey Island. (This might be because of the music's rather strong nature, so it was as loud as the voice acting.) But the example in the article managed to prove the point very well.
I now think that Nintendo actually noticed it many years ago, as I don't know of one game they made with full voice acting. Also, when the characters do say something, their lines are often hated by the fans. ('Listen!')
Thank you for sharing this with us, MusicallyInspired!