The point I would like to make is are we attempting to create a High Fidelity recording or not?
Not.
First of all, high fidelity is a misleading term, as I've said already. Fidelity implies that the recording should be accurate in relation to… something. What is that thing? If a completely acoustical sound is captured by a microphone and not processed at all, then there is a way to know how much fidelity there is in a system that tries to recreate that sound. in all other cases, there is no "original" sound source to have fidelity for.
All music today is recorded and mixed in a way that does not even attempt to maintain the acoustical fidelity of a performance. That is not a criticism – this is a description of reality. The reason it is done like that is because live acoustic music is very limited. Instruments mask each other and collide in their spectrum, any reverbs or echo in the space makes everything wash out and blend together, and volume levels of different instruments are rarely well matched. In the old days before recordings were possible, people worked around these limitations – to play a tympani together with a violin, you need several violins to play in unison to try and match the tympani's volume. Masking and washing out of many instruments playing together was used to create a unified sound field – for a lack of better option. If you wanted to hear individual instruments play together, you needed to use very few instruments, and sit very close (like string quartets).
With the advent of recording techniques and digital sound processes, we are no longer bound by the limitations of acoustical instruments. A single guitar can be as loud as a drum-set if so desired. There is no real need to limit ourselves to the performance of raw instruments, and thus there is no point in maintaining so-called fidelity. Engineers are close-miking instruments to get the cleanest sound, and then compress, EQ, and add reverb to create a desired sound signature that will fit the music. With these techniques they are able to achieve sounds and mixes that are virtually impossible in a pure untouched live performance. And this is not a bad thing that we should fight against – this is the very nature of the music industry today.
Some of the tools that are employed to achieve these ends are compression and limiting. On the far end of the chain, after the musician has played their tune and the engineer mixed it and the producer was happy and went home, there sits some audiophile and analyzes their hard work with a very basic algorithm that spits out a single number. And for him that single number is the absolute arbiter to whether the people that made the music did a good job or not. This is utterly ridiculous.
I've never been to a modern heavy metal concert but I imagine even they have higher dynamics live than they do on disc.
As for heavy metal – albums always sound better than performances, no doubt. It's almost impossible to create a live mix that maintain separation and coherence with a lot of loud, often natively distorted instruments, that are played aggressively. You go for the shows not for sound quality (which is 99% shit), but to see your heroes play live and cheer for them. there have been shows of major bands that sounded so awful that I had to complete some of the instrument parts in my head from memory.
Here is an example of a metal album the had been remastered and it's DR reduced:
The remaster is much more coherent and engaging than the original recording. There have probably been some EQ added which made most of the improvement, by I don't feel any difference in terms of dynamics. It's just sound tighter and more awesome.
On the other hand, Testament re-released an album with higher DR than the original:
And for me it sounds thinner and less engaging. The bass became distant and not immediate like the original release, and the cymbals became piercing and obnoxious.
And for the record, just so no-one can claim otherwise, I'm not listening to these things in the car or in noisy environment. These are my observation listening to my main system, or through my high fidelity headphones.