Not to be repetitive but some reasons why the fuse is actually critical include but are not limited to it’s exposed to RFI, it’s exposed to vibration, it’s exposed to magnetic fields, it’s a conductor, thus purer and/or better metal conductors and end caps are audible. For starters I would specify 5 nines silver or 7 nines copper for the fuse wire, end caps and the fuse holder. It's not rocket science, folks.Bingo. From my own personal experience, it took a couple of days for the new fuses to break in while playing 24/7, just like any new cable or component.
Now before anyone counters with how can something so small need to be broken in, think about all the discussion about capacitors, connectors, cables and the like needing some time to break in. This is generally agreed upon.
The act of removing and inserting terminations which removes motes of oxidation has been made to discount just what actually is responsible, as has extremely small matters as turn on and warm up time needing to be exactly the same, time of day, weather conditions, seating position, frame of mind, etc and yet some other thing as small as a fuse is to be discounted?
Gentlemen, you are arguing against yourselves.
All the best,
Nonoise