@Aedes,
You're right about Mustaine... I coulda swore... oh well.
As for Lars, he was never a brilliant player. ...And Justice took him over a year to lay down. But they are great tracks, definitely Lar's best.
Justice was a unique record. Great progressive metal, but it's so damn dry. The bass is way back, and that makes the drums all the more important. I never understood why Metallica did this, maybe because Jason was new, but it worked out. It makes the record all the more compelling... as you say, "ponderous". Had Justice been as wet as Master or, gulp, Black Album, you would not hear people argue that it was Metallica's best.
This newest Metallica album is an improvement over St. Anger, but when I look back at the incredible art the band once put out I just can't bring myself to think much of the band's latest efforts. The same is true of 311 - both bands are getting old, I suppose, and the music is high energy. Tough to keep up.
The one good thing about the current incarnation of Metallica is that bassist. I liked Jason, but Trujilo is a monster.