This comparison between TBA and the 80s albums has gone fuckin insane! Like I said there are similarities AND differences.
James Hetfield even says in A Year and A Half in the Life Of Metallica that they deliberately overhauled their songwriting formula, focusing on a few core riffs rather than elaborate, lengthy riffage; slowing the tempo; downtuning the guitar (first time ever done for Metallica on TBA); etc. These are Hetfield's word fella.
There is also the production element. TBA is a crisp, clean, smooth record. All the notes and drum hits are delivered with perfection because the album is so heavily produced with the 1990s analogue equivalent of pro-tools and MULTIPLE takes. TBA is a bass heavy disc, lots of low end on all the intruments. Sometimes there are FOUR guitar tracks per riffs laid down (in the 1980s they used to do a left+right, excl solos, harmonies, melodies).
What other elements were introduced to the sound on the TBA. Fucking u name it, sitars, shakers, tamborines, vibraphones, and a bunch of other exotic shit which I have no idea what it's all called.
I could go on but this is a waste of my time. Pray tell us stompmosher, what, in your opinion, IS thrash metal? Please, be exhaustive, but please be concise.
You also missing the point about 'genre' - obviously categorising things in this way inherently entails generalisation. RtL is a thrash metal album. But I'll await your definition of thrash before we go there...